Working with Digital Signature
3 Sep 2020 / 24 minutes to read
Adding a digital signature
The Essential PDF allows you to add digital signature to the PDF document. To add digital signature, you need a certificate with private keys. The Essential PDF provides support for digital signature by using PFX files, Hardware Security Module(HSM), Online Certificate Status Protocol (OCSP), Certificate Revocation List (CRL), and Windows Certificate Store.
The following code example explains how to add a digital signature to the PDF document.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
PdfCertificate pdfCert = new PdfCertificate(@"PDF.pfx", "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(@"signature.jpg");
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Saves and closes the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPageBase = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from PFX file with private key
Dim pdfCert As New PdfCertificate("PDF.pfx", "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(document, page, pdfCert, "Signature")
'Sets an image for signature field
Dim signatureImage As New PdfBitmap("signature.jpg")
'Sets signature info
signature.Bounds = New RectangleF(New PointF(0, 0), signatureImage.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(signatureImage, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
FileStream imageStream = new FileStream("signature.jpg", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Adding a digital signature using stream
The following code example illustrates how to add a digital signature in the PDF document
using stream as follows.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Gets a stream from .pfx file
Stream pfxStream = File.OpenRead("PDF.pfx");
//Creates a certificate instance from PFX file stream with private key
PdfCertificate pdfCert = new PdfCertificate(pfxStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(@"signature.jpg");
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Saves and closes the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPageBase = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Gets stream from .pfx file
Dim pfxStream As Stream = File.OpenRead("PDF.pfx")
'Creates a certificate instance from PFX file stream with private key
Dim pdfCert As New PdfCertificate(pfxStream, "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(document, page, pdfCert, "Signature")
'Sets an image for signature field
Dim signatureImage As New PdfBitmap("signature.jpg")
'Sets signature information
signature.Bounds = New RectangleF(New PointF(0, 0), signatureImage.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(signatureImage, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
FileStream imageStream = new FileStream("signature.jpg", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("sample.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("sample.pdf", "application/pdf", stream);
}You can add a digital signature to an existing document as follows.
//Loads the PDF document with signature field
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//Gets the page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a signature field
PdfSignatureField signatureField = new PdfSignatureField(page, "SignatureField");
signatureField.Bounds = new RectangleF(0, 0, 100, 100);
signatureField.Signature = new PdfSignature();
//Adds certificate to the signature field
signatureField.Signature.Certificate = new PdfCertificate(@"PDF.pfx", "syncfusion");
signatureField.Signature.Reason = "I am author of this document";
//Adds the field
loadedDocument.Form.Fields.Add(signatureField);
//Saves the certified PDF document
loadedDocument.Save(@"Output.pdf");
loadedDocument.Close(true);'Loads the PDF document with signature field
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'Gets the page
Dim page As PdfLoadedPage = TryCast(loadedDocument.Pages(0), PdfLoadedPage)
'Creates a signature field
Dim signatureField As New PdfSignatureField(page, "SignatureField")
signatureField.Bounds = New RectangleF(0, 0, 100, 100)
signatureField.Signature = New PdfSignature()
'Adds certificate to the signature field
signatureField.Signature.Certificate = New PdfCertificate("PDF.pfx", "syncfusion")
signatureField.Signature.Reason = "I am author of this document"
'Adds the field
loadedDocument.Form.Fields.Add(signatureField)
'Saves the certified PDF document
loadedDocument.Save("Output.pdf")
loadedDocument.Close(True)//Create the file open picker
var picker = new FileOpenPicker();
picker.FileTypeFilter.Add(".pdf");
//Browse and chose the file
StorageFile file = await picker.PickSingleFileAsync();
//Creates an empty PDF loaded document instance
PdfLoadedDocument loadedDocument = new PdfLoadedDocument();
//Loads or opens an existing PDF document through Open method of PdfLoadedDocument class
await loadedDocument.OpenAsync(file);
//Gets the page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a signature field
PdfSignatureField signatureField = new PdfSignatureField(page, "SignatureField");
signatureField.Bounds = new RectangleF(0, 0, 100, 100);
signatureField.Signature = new PdfSignature();
//Adds certificate to the signature field
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.
signatureField.Signature.Certificate = new PdfCertificate(certificateStream, "syncfusion");
signatureField.Signature.Reason = "I am author of this document";
//Adds the field
loadedDocument.Form.Fields.Add(signatureField);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await loadedDocument.SaveAsync(stream);
//Close the document
loadedDocument.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a signature field
PdfSignatureField signatureField = new PdfSignatureField(page, "SignatureField");
signatureField.Bounds = new RectangleF(0, 0, 100, 100);
signatureField.Signature = new PdfSignature();
//Adds certificate to the signature field
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
signatureField.Signature.Certificate = new PdfCertificate(certificateStream, "syncfusion");
signatureField.Signature.Reason = "I am author of this document";
//Adds the field
loadedDocument.Form.Fields.Add(signatureField);
//Save the document into stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Close the documents
loadedDocument.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Load the file as stream
Stream docStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf");
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a signature field
PdfSignatureField signatureField = new PdfSignatureField(page, "SignatureField");
signatureField.Bounds = new RectangleF(0, 0, 100, 100);
signatureField.Signature = new PdfSignature();
//Adds certificate to the signature field
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
signatureField.Signature.Certificate = new PdfCertificate(certificateStream, "syncfusion");
signatureField.Signature.Reason = "I am author of this document";
//Adds the field
loadedDocument.Form.Fields.Add(signatureField);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
//Closes the document
loadedDocument.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Adding a digital signature using X509Certificate2
The following code example illustrates how to add digital signature in a PDF document using X509Certificate2 as follows.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
X509Certificate2 certificate = new X509Certificate2("PDF.pfx", "syncfusion");
PdfCertificate pdfCertificate = new PdfCertificate(certificate);
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCertificate, "Signature");
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(@"signature.jpg");
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document
document.Save("Output.pdf");
//Close the document
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPage = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from PFX file with private key
Dim certificate As New X509Certificate2("PDF.pfx", "syncfusion")
Dim pdfCertificate As New PdfCertificate(certificate)
'Creates a digital signature
Dim signature As New PdfSignature(document, page, pdfCertificate, "Signature")
'Sets an image for signature field
Dim signatureImage As New PdfBitmap("signature.jpg")
'Sets signature information
signature.Bounds = New RectangleF(New PointF(0, 0), signatureImage.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(signatureImage, 0, 0)
'Save the document
document.Save("Output.pdf")
'Close the document
document.Close(True)//Essential PDF supports adding a digital signature using X509Certificate2 only in Windows Forms, WPF, ASP.NET, ASP.NET MVC, and ASP.NET Core platforms.//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
X509Certificate2 certificate = new X509Certificate2("PDF.pfx", "syncfusion");
PdfCertificate pdfCertificate = new PdfCertificate(certificate);
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCertificate, "Signature");
//Sets an image for signature field
FileStream imageStream = new FileStream("signature.jpg", FileMode.Open, FileAccess.Read);
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Creating the stream object
MemoryStream stream = new MemoryStream();
//Save the document as stream
document.Save(stream);
//If the position is not set to '0', then the PDF will be empty
stream.Position = 0;
//Close the document
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
MemoryStream ms = new MemoryStream();
certificateStream.CopyTo(ms);
X509Certificate2 certificate = new X509Certificate2(ms.ToArray(), "syncfusion");
PdfCertificate pdfCertificate = new PdfCertificate(certificate);
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCertificate, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document as stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Close the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.RuntimePlatform == Device.UWP)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Signing an existing document
You can load the signature field from the existing PDF document and add certificate to the document as follows.
//Loads a PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
PdfCertificate certificate = new PdfCertificate(@"PDF.pfx", "syncfusion");
field.Signature = new PdfSignature(loadedDocument,page,certificate,"Signature",field);
//Saves the document
loadedDocument.Save("Output.pdf");
//Closes the document
loadedDocument.Close(true);'Loads a PDF document
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'Gets the first page of the document
Dim page As PdfLoadedPage = TryCast(loadedDocument.Pages(0), PdfLoadedPage)
'Gets the first signature field of the PDF document
Dim field As PdfLoadedSignatureField = TryCast(loadedDocument.Form.Fields(0), PdfLoadedSignatureField)
'Creates a certificate
Dim certificate As New PdfCertificate("PDF.pfx", "syncfusion")
field.Signature = New PdfSignature(loadedDocument, page, certificate, "Signature", field)
'Saves the document
loadedDocument.Save("Output.pdf")
'Closes the document
loadedDocument.Close(True)//Create the file open picker
var picker = new FileOpenPicker();
picker.FileTypeFilter.Add(".pdf");
//Browse and chose the file
StorageFile file = await picker.PickSingleFileAsync();
//Creates an empty PDF loaded document instance
PdfLoadedDocument loadedDocument = new PdfLoadedDocument();
//Loads or opens an existing PDF document through Open method of PdfLoadedDocument class
await loadedDocument.OpenAsync(file);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.
PdfCertificate certificate = new PdfCertificate(certificateStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await loadedDocument.SaveAsync(stream);
//Close the document
loadedDocument.Close(true);
//Save the stream as PDF document file in local machine. Refer to PDF/UWP section for respected code samples
Save(stream, "Output.pdf");//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate certificate = new PdfCertificate(certificateStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Save the document into stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Close the documents
loadedDocument.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Load the file as stream
Stream docStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Sample.pdf");
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate certificate = new PdfCertificate(certificateStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
//Closes the document
loadedDocument.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Sign an existing document using stream
You can load the signature field from an existing PDF document and add certificate to the document using stream as follows.
//Loads a PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Gets the stream from .pfx file
Stream pfxStream = File.OpenRead("PDF.pfx");
//Creates a certificate instance from PFX file stream with private key
PdfCertificate certificate = new PdfCertificate(pfxStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Saves the document
loadedDocument.Save("Output.pdf");
//Closes the document
loadedDocument.Close(true);'Loads a PDF document
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'Gets the first page of the document
Dim page As PdfLoadedPage = TryCast(loadedDocument.Pages(0), PdfLoadedPage)
'Gets the first signature field of the PDF document
Dim field As PdfLoadedSignatureField = TryCast(loadedDocument.Form.Fields(0), PdfLoadedSignatureField)
'Gets the stream from .pfx file
Dim pfxStream As Stream = File.OpenRead("PDF.pfx")
'Creates a certificate instance from PFX file stream with private key
Dim certificate As New PdfCertificate(pfxStream, "syncfusion")
field.Signature = New PdfSignature(loadedDocument, page, certificate, "Signature", field)
'Saves the document
loadedDocument.Save("Output.pdf")
'Closes the document
loadedDocument.Close(True)//Create the file open picker
var picker = new FileOpenPicker();
picker.FileTypeFilter.Add(".pdf");
//Browse and chose the file
StorageFile file = await picker.PickSingleFileAsync();
//Creates an empty PDF loaded document instance
PdfLoadedDocument loadedDocument = new PdfLoadedDocument();
//Loads or opens an existing PDF document through Open method of PdfLoadedDocument class
await loadedDocument.OpenAsync(file);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate certificate = new PdfCertificate(certificateStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await loadedDocument.SaveAsync(stream);
//Close the document
loadedDocument.Close(true);
//Save the stream as PDF document file in local machine. Refer to PDF/UWP section for respected code samples
Save(stream, "output.pdf");//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate certificate = new PdfCertificate(certificateStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Save the document into stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Close the documents
loadedDocument.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Load the file as stream
Stream docStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Sample.pdf");
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField field = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Creates a certificate
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate certificate = new PdfCertificate(certificateStream, "syncfusion");
field.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", field);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
//Closes the document
loadedDocument.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Externally sing a PDF document
You can sign the PDF document from external digital signature created from various sources such as HSM, USB token, smart card, or other cloud services such as DigitalSign.
The following code example shows how to sign the PDF document from external signature.
//Load existing PDF document
PdfLoadedDocument document = new PdfLoadedDocument("PDF_Succinctly.pdf");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, document.Pages[0], null, "DigitalSignature");
signature.ComputeHash += Signature_ComputeHash;
//Save the PDF document
document.Save("ExternalSignature.pdf");
//Close the document
document.Close(true);
void Signature_ComputeHash(object sender, PdfSignatureEventArgs arguments)
{
//Get the document bytes
byte[] documentBytes = arguments.Data;
SignedCms signedCms = new SignedCms(new ContentInfo(documentBytes), detached: true);
//Compute the signature using the specified digital ID file and the password
X509Certificate2 certificate = new X509Certificate2("DigitalSignatureTest.pfx", "DigitalPass123");
var cmsSigner = new CmsSigner(certificate);
//Set the digest algorithm SHA256
cmsSigner.DigestAlgorithm = new Oid("2.16.840.1.101.3.4.2.1");
signedCms.ComputeSignature(cmsSigner);
//Embed the encoded digital signature to the PDF document
arguments.SignedData = signedCms.Encode();
}'Load existing PDF document
Dim document As PdfLoadedDocument = New PdfLoadedDocument("PDF_Succinctly.pdf")
'Creates a digital signature
Dim signature As PdfSignature = New PdfSignature(document, document.Pages(0), Nothing, "DigitalSignature")
signature.ComputeHash += Signature_ComputeHash
'Save the PDF document
document.Save("ExternalSignature.pdf")
'Close the document
document.Close(True)
Private Sub Signature_ComputeHash(ByVal sender As Object, ByVal arguments As PdfSignatureEventArgs)
'Get the document bytes
Dim documentBytes As Byte() = arguments.Data
Dim signedCms As SignedCms = New SignedCms(New ContentInfo(documentBytes), detached:=True)
'Compute the signature using the specified digital ID file and the password
Dim certificate As X509Certificate2 = New X509Certificate2("DigitalSignatureTest.pfx", "DigitalPass123")
Dim cmsSigner = New CmsSigner(certificate)
'Set the digest algorithm SHA256
cmsSigner.DigestAlgorithm = New Oid("2.16.840.1.101.3.4.2.1")
signedCms.ComputeSignature(cmsSigner)
'Embed the encoded digital signature to the PDF document
arguments.SignedData = signedCms.Encode()
End Sub//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data. PDF_Succinctly.pdf");
//Load an existing signed PDF document
PdfLoadedDocument document = new PdfLoadedDocument(documentStream);
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, document.Pages[0], null, "DigitalSignature");
signature.ComputeHash += Signature_ComputeHash;
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, " ExternalSignature.pdf");
private static void Signature_ComputeHash1(object sender, PdfSignatureEventArgs ars)
{
//Get the document bytes
byte[] documentBytes = ars.Data;
SignedCms signedCms = new SignedCms(new ContentInfo(documentBytes), detached: true);
//Compute the signature using the specified digital ID file and the password
X509Certificate2 certificate = new X509Certificate2("DigitalSignatureTest.pfx", "DigitalPass123");
var cmsSigner = new CmsSigner(certificate);
//Set the digest algorithm SHA256
cmsSigner.DigestAlgorithm = new Oid("2.16.840.1.101.3.4.2.1");
signedCms.ComputeSignature(cmsSigner);
//Embed the encoded digital signature to the PDF document
ars.SignedData = signedCms.Encode();
}//Get the stream from the document
FileStream documentStream = new FileStream("PDF_Succinctly.pdf ", FileMode.Open, FileAccess.Read);
//Load the existing PDF document
PdfLoadedDocument document = new PdfLoadedDocument(documentStream);
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, document.Pages[0], null, "DigitalSignature");
signature.ComputeHash += Signature_ComputeHash;
MemoryStream ms = new MemoryStream();
document.Save(ms);
document.Close(true);
private static void Signature_ComputeHash1(object sender, PdfSignatureEventArgs ars)
{
//Get the document bytes
byte[] documentBytes = ars.Data;
SignedCms signedCms = new SignedCms(new ContentInfo(documentBytes), detached: true);
//Compute the signature using the specified digital ID file and the password
X509Certificate2 certificate = new X509Certificate2("DigitalSignatureTest.pfx", "DigitalPass123");
var cmsSigner = new CmsSigner(certificate);
//Set the digest algorithm SHA256
cmsSigner.DigestAlgorithm = new Oid("2.16.840.1.101.3.4.2.1");
signedCms.ComputeSignature(cmsSigner);
//Embed the encoded digital signature to the PDF document
ars.SignedData = signedCms.Encode();
}//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF_Succinctly.pdf");
//Load an existing signed PDF document
PdfLoadedDocument document = new PdfLoadedDocument(documentStream);
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, document.Pages[0], null, "DigitalSignature");
signature.ComputeHash += Signature_ComputeHash;
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into pdf file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("ExternalSignature.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("ExternalSignature.pdf", "application/pdf", stream);
}
private static void Signature_ComputeHash1(object sender, PdfSignatureEventArgs ars)
{
//Get the document bytes
byte[] documentBytes = ars.Data;
SignedCms signedCms = new SignedCms(new ContentInfo(documentBytes), detached: true);
//Compute the signature using the specified digital ID file and the password
X509Certificate2 certificate = new X509Certificate2("DigitalSignatureTest.pfx", "DigitalPass123");
var cmsSigner = new CmsSigner(certificate);
//Set the digest algorithm SHA256
cmsSigner.DigestAlgorithm = new Oid("2.16.840.1.101.3.4.2.1");
signedCms.ComputeSignature(cmsSigner);
//Embed the encoded digital signature to the PDF document
ars.SignedData = signedCms.Encode();
}Create Long Term Validation (LTV) when signing PDF documents externally
You can create a Long Term validation (LTV) when signing PDF documents externally using your private/public certificates.
The following code example shows how to create an LTV when signing a PDF document from external signature.
//Load an existing PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//Get the page of the existing PDF document
PdfLoadedPage loadedPage = loadedDocument.Pages[0] as PdfLoadedPage;
//Create a new PDF signature without PdfCertificate instance
PdfSignature signature = new PdfSignature(loadedDocument, loadedPage, null, "Signature1");
//Hook up the ComputeHash event
signature.ComputeHash += Signature_ComputeHash;
//Create X509Certificate2 from your certificate to create a long-term validity
X509Certificate2 x509 = new X509Certificate2("PDF.pfx", "password123");
//Create LTV with your public certificates
signature.CreateLongTermValidity(new List<X509Certificate2> { x509 });
//Save and close the PDF document
loadedDocument.Save("SignedDocument.pdf");
loadedDocument.Close(true);'Load an existing PDF document
Dim loadedDocument As PdfLoadedDocument = New PdfLoadedDocument("Input.pdf")
'Get the page of the existing PDF document
Dim loadedPage As PdfLoadedPage = TryCast(loadedDocument.Pages(0), PdfLoadedPage)
'Create a new PDF signature without PdfCertificate instance
Dim signature As PdfSignature = New PdfSignature(loadedDocument, loadedPage, Nothing, "Signature1")
' Hook up the ComputeHash event
AddHandler signature.ComputeHash, AddressOf Signature_ComputeHash
'Create X509Certificate2 from your certificate to create a long-term validity
Dim x509 As X509Certificate2 = New X509Certificate2("PDF.pfx", "password123")
'Create LTV with your public certificates
signature.CreateLongTermValidity(New List(Of X509Certificate2) From { x509 })
'Save and close the PDF document
loadedDocument.Save("SignedDocument.pdf")
loadedDocument.Close(True)//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf");
//Load an existing PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//Get the page of the existing PDF document
PdfLoadedPage loadedPage = loadedDocument.Pages[0] as PdfLoadedPage;
//Create a new PDF signature without PdfCertificate instance
PdfSignature signature = new PdfSignature(loadedDocument, loadedPage, null, "Signature1");
//Hook up the ComputeHash event
signature.ComputeHash += Signature_ComputeHash;
//Create X509Certificate2 from your certificate to create a long-term validity
X509Certificate2 x509 = new X509Certificate2("PDF.pfx", "password123");
//Create LTV with your public certificates
signature.CreateLongTermValidity(new List<X509Certificate2> { x509 });
//Save the PDF document
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Get the stream from the document
FileStream documentStream = new FileStream("Input.pdf ", FileMode.Open, FileAccess.Read);
//Load an existing PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//Get the page of the existing PDF document
PdfLoadedPage loadedPage = loadedDocument.Pages[0] as PdfLoadedPage;
//Create a new PDF signature without PdfCertificate instance
PdfSignature signature = new PdfSignature(loadedDocument, loadedPage, null, "Signature1");
//Hook up the ComputeHash event
signature.ComputeHash += Signature_ComputeHash;
//Create X509Certificate2 from your certificate to create a long-term validity
X509Certificate2 x509 = new X509Certificate2("PDF.pfx", "password123");
//Create LTV with your public certificates
signature.CreateLongTermValidity(new List<X509Certificate2> { x509 });
//Save the PDF document
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Close the document
loadedDocument.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a File object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets. Input.pdf");
//Load an existing PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//Get the page of the existing PDF document
PdfLoadedPage loadedPage = loadedDocument.Pages[0] as PdfLoadedPage;
//Create a new PDF signature without PdfCertificate instance
PdfSignature signature = new PdfSignature(loadedDocument, loadedPage, null, "Signature1");
//Hook up the ComputeHash event
signature.ComputeHash += Signature_ComputeHash;
//Create X509Certificate2 from your certificate to create a long-term validity
X509Certificate2 x509 = new X509Certificate2("PDF.pfx", "password123");
//Create LTV with your public certificates
signature.CreateLongTermValidity(new List<X509Certificate2> { x509 });
//Save the PDF document
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Save the stream into pdf file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Adding a signature validation appearance based on the signature
You can add the dynamic signature validation appearance to the signature field by enabling the “EnableValidationAppearance” property available in the “PdfSignature” class, the appearance will change based on the PDF reader validation.
Refer to the following code sample.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Add a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics=page.Graphics;
//Creates a certificate instance from the PFX file with private key
PdfCertificate pdfCert = new PdfCertificate(@"PDF.pfx", "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for the signature field
PdfBitmap signatureImage = new PdfBitmap(@"signature.jpg");
//Sets enable signature validation appearance
signature.EnableValidationAppearance = true;
//Sets signature information
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draw the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save and close documents
document.Save("Output.pdf");
document.Close( true );'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPageBase = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from the PFX file with private key
Dim pdfCert As New PdfCertificate("PDF.pfx", "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(document, page, pdfCert, "Signature")
'Sets an image for the signature field
Dim signatureImage As New PdfBitmap("signature.jpg")
‘Sets enable signature validation appearance
signature.EnableValidationAppearance = True
'Sets signature info
signature.Bounds = New RectangleF(New PointF(0, 0), signatureImage.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(signatureImage, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from the PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets enable signature validation appearance
signature.EnableValidationAppearance = true;
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from the PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for the signature field
FileStream imageStream = new FileStream("signature.jpg", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets enable signature validation appearance
signature.EnableValidationAppearance = true;
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for PDF file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from the PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for the signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets enable signature validation appearance
signature.EnableValidationAppearance = true;
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples.
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Adding a timestamp in digital signature
Essential PDF allows you to add timestamp in the digital signature of the PDF document. The following code example explains the same.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
PdfCertificate pdfCert = new PdfCertificate(@"PDF.pfx", "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, pdfCert, "Signature");
//Sets an image for signature field
PdfBitmap image = new PdfBitmap(@"syncfusion_logo.gif");
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Saves and closes the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPage = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from PFX file with private key
Dim pdfCert As New PdfCertificate("PDF.pfx", "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(page, pdfCert, "Signature")
'Sets an image for signature field
Dim image As New PdfBitmap("syncfusion_logo.gif")
'Adds time stamp by using the server URI and credentials
signature.TimeStampServer = New TimeStampServer(New Uri("http://syncfusion.digistamp.com"), "user", "123456")
'Sets signature info
signature.Bounds = New RectangleF(New PointF(0, 0), image.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(image, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.syncfusion_logo.gif");
PdfBitmap image = new PdfBitmap(imageStream);
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
FileStream imageStream = new FileStream("syncfusion_logo.gif", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap image = new PdfBitmap(imageStream);
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.syncfusion_logo.gif");
PdfBitmap image = new PdfBitmap(imageStream);
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("sample.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("sample.pdf", "application/pdf", stream);
}Adding a timestamp to PDF document
You can add timestamp to the PDF document using the following code snippet.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Save and close the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPage = document.Pages.Add()
'Creates a digital signature
Dim signature As New PdfSignature(page, "Signature")
'Adds time stamp by using the server URI
signature.TimeStampServer = New TimeStampServer(New Uri("http://syncfusion.digistamp.com"), "user", "123456")
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Create a new document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to PDF/UWP section for respected code samples.
Save(stream, "Output.pdf");//Create a new pdf document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Save the document into stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Close the document
loadedDocument.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Create a new PDF document
PdfDocument document = new PdfDocument();
//Add a page
PdfPage page = document.Pages.Add();
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
document.Save(memoryStream);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples.
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", memoryStream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", memoryStream);
}Adding a timestamp to existing PDF document
You can add timestamp to the existing PDF document using the following code snippet.
//Load the existing PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//Add a new page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Saves the document
loadedDocument.Save("Output.pdf");
//Closes the document
loadedDocument.Close(true);'Load the PDF document
Dim document As New PdfLoadedDocument("Input.pdf")
'Gets the first page of the document
Dim page As PdfLoadedPage = TryCast(document.Pages(0), PdfLoadedPage)
'Creates a digital signature
Dim signature As New PdfSignature(page, "Signature")
'Adds time stamp by using the server URI
signature.TimeStampServer = New TimeStampServer(New Uri("http://syncfusion.digistamp.com"), "user", "123456")
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Create the file open picker
var picker = new FileOpenPicker();
picker.FileTypeFilter.Add(".pdf");
//Browse and chose the file
StorageFile file = await picker.PickSingleFileAsync();
//Creates an empty PDF loaded document instance
PdfLoadedDocument loadedDocument = new PdfLoadedDocument();
//Loads or opens an existing PDF document through Open method of PdfLoadedDocument class
await loadedDocument.OpenAsync(file);
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
MemoryStream stream = new MemoryStream();
await loadedDocument.SaveAsync(stream);
//Close the document.
loadedDocument.Close(true);
//Save the stream as PDF document file in local machine. Refer to PDF/UWP section for respected code samples
Save(stream, "Output.pdf");//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a digital signature.
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Save the document into stream
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
stream.Position = 0;
//Close the document
loadedDocument.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Load the file as stream
Stream docStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf ");
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Gets the page
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, "Signature");
//Add the time stamp by using the server URI
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456")
//Save the PDF document to stream
MemoryStream memoryStream = new MemoryStream();
loadedDocument.Save(memoryStream);
//Closes the document
loadedDocument.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", memoryStream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", memoryStream);
}Retrieve certificate details from an existing signed PDF document
The Essential PDF provides support to get the certificate details from an existing signed PDF document such as,
- Signed date
- Expiry date
- Signed name
- Subject name
- Issuer name
- Certificate distinguished names (country, state, street, email, organization, organization unit, locality, and more).
You can get the above certificate details from an existing signed PDF document by using the following code snippet.
//Load the existing signed PDF
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("SignedDocument.pdf");
//Load the PDF form
PdfLoadedForm loadedForm = loadedDocument.Form as PdfLoadedForm;
//Get the signature field
PdfLoadedSignatureField signatureField = loadedForm.Fields[0] as PdfLoadedSignatureField;
//Get the certificate
PdfCertificate certificate = signatureField.Signature.Certificate;
//Get the signed date
DateTime date = signatureField.Signature.SignedDate;
//Get the signed name
string name = signatureField.Signature.SignedName;
//Get the certificate names based on their distinguished name.
string subjectName = certificate.SubjectName;
string subjectCountry = certificate.GetValue(PdfCertificateDistinguishedName.Country, PdfCertificateField.Subject);
string subjectOrganization = certificate.GetValue(PdfCertificateDistinguishedName.Organization, PdfCertificateField.Subject);
//Issuer details
string issuerName = certificate.IssuerName;
string issuerOrganization = certificate.GetValue(PdfCertificateDistinguishedName.Organization, PdfCertificateField.Issuer);
string issuerCountry = certificate.GetValue(PdfCertificateDistinguishedName.Country, PdfCertificateField.Issuer);
//Get certificate validation date information
DateTime validFrom = certificate.ValidFrom;
DateTime validTo = certificate.ValidTo;
//Close the document
loadedDocument.Close(true);'Load the existing signed PDF
Dim loadedDocument As PdfLoadedDocument = New PdfLoadedDocument("../../Signed.pdf")
'Load the PDF form
Dim loadedForm As PdfLoadedForm = TryCast(loadedDocument.Form, PdfLoadedForm)
'Get the signature field
Dim signatureField As PdfLoadedSignatureField = TryCast(loadedForm.Fields(0), PdfLoadedSignatureField)
'Get the certificate
Dim certificate As PdfCertificate = signatureField.Signature.Certificate
'Get the signed date
Dim signedDate As DateTime = signatureField.Signature.SignedDate
'Get the signed name
Dim name As String = signatureField.Signature.SignedName
'Get the certificate names based on their distinguished name
Dim subjectName As String = certificate.SubjectName
Dim subjectCountry As String = certificate.GetValue(PdfCertificateDistinguishedName.Country, PdfCertificateField.Subject)
Dim subjectOrganization As String = certificate.GetValue(PdfCertificateDistinguishedName.Organization, PdfCertificateField.Subject)
'Issuer details
Dim issuerName As String = certificate.IssuerName
Dim issuerOrganization As String = certificate.GetValue(PdfCertificateDistinguishedName.Organization, PdfCertificateField.Issuer)
Dim issuerCountry As String = certificate.GetValue(PdfCertificateDistinguishedName.Country, PdfCertificateField.Issuer)
'Get certificate validation date information
Dim validFrom As DateTime = certificate.ValidFrom
Dim validTo As DateTime = certificate.ValidTo
loadedDocument.Close(True)//Essential PDF supports retrieving certificate details from signed PDF document only in Windows Forms, WPF, ASP.NET, and ASP.NET MVC platforms//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//Get the signature field
PdfLoadedSignatureField signatureField = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Get the certificate
PdfCertificate certificate = signatureField.Signature.Certificate;
//Get the signed date
DateTime date = signatureField.Signature.SignedDate;
//Get the signed name
string name = signatureField.Signature.SignedName;
//Gets the certificate subject's name
string subjectName = certificate.SubjectName;
//Gets the certificate issuer's name
string issuerName = certificate.IssuerName;
//Get certificate validation date information
DateTime validFrom = certificate.ValidFrom;
DateTime validTo = certificate.ValidTo;
//Close the document
loadedDocument.Close(true);//Essential PDF supports retrieving certificate details from signed PDF document only in Windows Forms, WPF, ASP.NET, and ASP.NET MVC platformsEnable Long Term Validation (LTV) PDF signature
The Essential PDF supports creating long term signature validation when signing the PDF document. The LTV signature allows you to check the validity of a signature long after the document was signed. To achieve long term validation, all the required elements for signature validation must be embedded in the signed PDF.
Note: The resulted PDF document size will be large since all the necessary signature information, Certificate Revocation List (CRL), and Online Certificate Status Protocol (OCSP) are embedded.
The following code example explains how to create LTV PDF.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPage page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
PdfCertificate pdfCert = new PdfCertificate(@"PDF.pfx", "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(page, pdfCert, "Signature");
//Sets an image for signature field
PdfBitmap image = new PdfBitmap(@"syncfusion_logo.gif");
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Enable LTV on Signature
signature.EnableLtv = true;
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Saves and closes the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPage = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from PFX file with private key
Dim pdfCert As New PdfCertificate("PDF.pfx", "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(page, pdfCert, "Signature")
'Sets an image for signature field
Dim image As New PdfBitmap("syncfusion_logo.gif")
'Adds time stamp by using the server URI and credentials
signature.TimeStampServer = New TimeStampServer(New Uri("http://syncfusion.digistamp.com"), "user", "123456")
'Enable LTV on Signature
signature.EnableLtv = True
'Sets signature info
signature.Bounds = New RectangleF(New PointF(0, 0), image.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(image, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.syncfusion_logo.gif");
PdfBitmap image = new PdfBitmap(imageStream);
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Enable LTV on Signature
signature.EnableLtv = true;
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to PDF/UWP section for respected code samples
Save(stream, "output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
FileStream imageStream = new FileStream("syncfusion_logo.gif", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap image = new PdfBitmap(imageStream);
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Enable LTV on Signature
signature.EnableLtv = true;
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.syncfusion_logo.gif");
PdfBitmap image = new PdfBitmap(imageStream);
//Adds time stamp by using the server URI and credentials
signature.TimeStampServer = new TimeStampServer(new Uri("http://syncfusion.digistamp.com"), "user", "123456");
//Enable LTV on Signature
signature.EnableLtv = true;
//Sets signature info
signature.Bounds = new RectangleF(new PointF(0, 0), image.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(image, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("output.pdf", "application/pdf", stream);
}Adding a digital signature with customization
The PdfSignatureSettings allows you to add customized digital signatures to the PDF document.
Adding a digital signature with CAdES format
As per the PDF specification 2.0, now Syncfusion PDF library supports digital signature based on CAdES (CMS Advanced Electronics Signature). The CAdES based digital signature can remain valid for long periods, even if underlying cryptographic algorithms are broken. Using the API CryptographicStandard, you can change the standard between CMS (Cryptographic Message Syntax) and CAdES.
The following code example explains how to add a digital signature with cryptographic standard (CAdES) to the PDF document.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
PdfCertificate pdfCert = new PdfCertificate(@"PDF.pfx", "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize cryptographic standard specified
PdfSignatureSettings settings = signature.Settings;
settings.CryptographicStandard = CryptographicStandard.CADES;
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(@"signature.jpg");
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Saves and closes the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPageBase = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from PFX file with private key
Dim pdfCert As New PdfCertificate("PDF.pfx", "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(document, page, pdfCert, "Signature")
'Sets signature settings to customize cryptographic standard specified
Dim settings As PdfSignatureSettings = signature.Settings
settings.CryptographicStandard = CryptographicStandard.CADES
'Sets an image for signature field
Dim signatureImage As New PdfBitmap("signature.jpg")
'Sets signature info
signature.Bounds = New RectangleF(New PointF(0, 0), signatureImage.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(signatureImage, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize cryptographic standard specified
PdfSignatureSettings settings = signature.Settings;
settings.CryptographicStandard = CryptographicStandard.CADES;
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize cryptographic standard specified
PdfSignatureSettings settings = signature.Settings;
settings.CryptographicStandard = CryptographicStandard.CADES;
//Sets an image for signature field
FileStream imageStream = new FileStream("signature.jpg", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize cryptographic standard specified
PdfSignatureSettings settings = signature.Settings;
settings.CryptographicStandard = CryptographicStandard.CADES;
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Customize digestion algorithm
In addition, you can now set the different message digest algorithm to sign PDF document using the DigestAlgorithm enum available in the class PdfSignatureSettings.
The following message digest algorithms are now supported:
- SHA1
- SHA256
- SHA384
- SHA512
- RIPEMD160
The following code example explains how to add a digital signature with various digest algorithms to the PDF document.
//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
PdfCertificate pdfCert = new PdfCertificate(@"PDF.pfx", "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize digest algorithm specified
PdfSignatureSettings settings = signature.Settings;
settings.DigestAlgorithm = DigestAlgorithm.SHA256;
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(@"signature.jpg");
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Saves and closes the document
document.Save("Output.pdf");
document.Close(true);'Creates a new PDF document
Dim document As New PdfDocument()
'Adds a new page
Dim page As PdfPageBase = document.Pages.Add()
Dim graphics As PdfGraphics = page.Graphics
'Creates a certificate instance from PFX file with private key
Dim pdfCert As New PdfCertificate("PDF.pfx", "syncfusion")
'Creates a digital signature
Dim signature As New PdfSignature(document, page, pdfCert, "Signature")
'Sets signature settings to customize digest algorithm specified
Dim settings As PdfSignatureSettings = signature.Settings
settings.DigestAlgorithm = DigestAlgorithm.SHA256
'Sets an image for signature field
Dim signatureImage As New PdfBitmap("signature.jpg")
'Sets signature info
signature.Bounds = New RectangleF(New PointF(0, 0), signatureImage.PhysicalDimension)
signature.ContactInfo = "johndoe@owned.us"
signature.LocationInfo = "Honolulu, Hawaii"
signature.Reason = "I am author of this document."
'Draws the signature image
graphics.DrawImage(signatureImage, 0, 0)
'Saves and closes the document
document.Save("Output.pdf")
document.Close(True)//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize digest algorithm specified
PdfSignatureSettings settings = signature.Settings;
settings.DigestAlgorithm = DigestAlgorithm.SHA256;
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
await document.SaveAsync(stream);
//Close the document
document.Close(true);
//Save the stream as PDF document file in local machine. Refer to the PDF/UWP section for respective code samples
Save(stream, "Output.pdf");//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize digest algorithm specified
PdfSignatureSettings settings = signature.Settings;
settings.DigestAlgorithm = DigestAlgorithm.SHA256;
//Sets an image for signature field
FileStream imageStream = new FileStream("signature.jpg", FileMode.Open, FileAccess.Read);
//Sets an image for signature field
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
stream.Position = 0;
//Close the documents
document.Close(true);
//Defining the ContentType for pdf file
string contentType = "application/pdf";
//Define the file name
string fileName = "Output.pdf";
//Creates a FileContentResult object by using the file contents, content type, and file name
return File(stream, contentType, fileName);//Creates a new PDF document
PdfDocument document = new PdfDocument();
//Adds a new page
PdfPageBase page = document.Pages.Add();
PdfGraphics graphics = page.Graphics;
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
PdfCertificate pdfCert = new PdfCertificate(certificateStream, "syncfusion");
//Creates a digital signature
PdfSignature signature = new PdfSignature(document, page, pdfCert, "Signature");
//Sets signature settings to customize digest algorithm specified
PdfSignatureSettings settings = signature.Settings;
settings.DigestAlgorithm = DigestAlgorithm.SHA256;
//Sets an image for signature field
Stream imageStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.signature.jpg");
PdfBitmap signatureImage = new PdfBitmap(imageStream);
//Sets signature information
signature.Bounds = new RectangleF(new PointF(0, 0), signatureImage.PhysicalDimension);
signature.ContactInfo = "johndoe@owned.us";
signature.LocationInfo = "Honolulu, Hawaii";
signature.Reason = "I am author of this document.";
//Draws the signature image
graphics.DrawImage(signatureImage, 0, 0);
//Save the PDF document to stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Closes the document
document.Close(true);
//Save the stream into PDF file
//The operation in Save under Xamarin varies between Windows Phone, Android, and iOS platforms. Refer to the PDF/Xamarin section for respective code samples
if (Device.OS == TargetPlatform.WinPhone || Device.OS == TargetPlatform.Windows)
{
Xamarin.Forms.DependencyService.Get<ISaveWindowsPhone>().Save("Output.pdf", "application/pdf", stream);
}
else
{
Xamarin.Forms.DependencyService.Get<ISave>().Save("Output.pdf", "application/pdf", stream);
}Digital signature validation
Added the support to validate the digital signatures in an existing PDF document. Digital signature validation covers the following steps to ensure the validity of the signatures:
- Validate the document modification.
- Validate the certificate chain.
- Ensure the signature with timestamp time.
- Check the revocation status of the certificate with OCSP and CRL.
- Ensure the multiple digital signatures.
You can use the ValidateSignature method available in the PdfLoadedSignatureField class to validate the digital signature.
You can get the overall status from the IsSignatureValid property available in the PdfSignatureValidationResult class.
The following code example explains how to validate the digitally signed PDF document signature.
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//Get signature field
PdfLoadedSignatureField signatureField = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2("PDF.pfx", "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate signature and get the validation result
PdfSignatureValidationResult result = signatureField.ValidateSignature(collection);
//Checks whether the signature is valid or not
SignatureStatus status = result.SignatureStatus;
//Checks whether the document is modified or not
bool isModified = result.IsDocumentModified;
//Signature details
string issuerName = signatureField.Signature.Certificate.IssuerName;
DateTime validFrom = signatureField.Signature.Certificate.ValidFrom;
DateTime validTo = signatureField.Signature.Certificate.ValidTo;
string signatureAlgorithm = result.SignatureAlgorithm;
DigestAlgorithm digestAlgorithm = result.DigestAlgorithm;
//Revocation validation details
RevocationResult revocationDetails = result.RevocationResult;
RevocationStatus revocationStatus = revocationDetails.OcspRevocationStatus;
bool isRevokedCRL = revocationDetails.IsRevokedCRL;
//Close the document
loadedDocument.Close(true);'Load an existing signed PDF document
Dim loadedDocument As PdfLoadedDocument = New PdfLoadedDocument("Input.pdf")
'Get signature field
Dim signatureField As PdfLoadedSignatureField = loadedDocument.Form.Fields[0] As PdfLoadedSignatureField
'X509Certificate2Collection to check the signer's identity using root certificates
Dim collection As X509CertificateCollection = New X509CertificateCollection()
'Create new X509Certificate2 with the root certificate
Dim certificate As X509Certificate2 = New X509Certificate2("PDF.pfx", "syncfusion")
'Add the certificate to the collection
collection.Add(certificate)
'Validate signature and get the validation result
Dim result As PdfSignatureValidationResult = signatureField.ValidateSignature(collection)
'Checks whether the signature is valid or not
Dim status As SignatureStatus = result.SignatureStatus
'Checks whether the document is modified or not
Dim isModified As Boolean = result.IsDocumentModified
'Signature details
Dim issuerName As String = signatureField.Signature.Certificate.IssuerName
Dim validFrom As DateTime = signatureField.Signature.Certificate.ValidFrom
Dim validTo As DateTime = signatureField.Signature.Certificate.ValidTo
Dim signatureAlgorithm As String = result.SignatureAlgorithm
Dim digestAlgorithm As DigestAlgorithm = result.DigestAlgorithm
'Revocation validation details
Dim revocationDetails As RevocationResult = result.RevocationResult
Dim revocationStatus As RevocationStatus = revocationDetails.OcspRevocationStatus
Dim isRevokedCRL As Boolean = revocationDetails.IsRevokedCRL
'Close the document
loadedDocument.Close(true)//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.Input.pdf");
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//Get signature field
PdfLoadedSignatureField signatureField = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
byte[] data = new byte[certificateStream.Length];
certificateStream.Read(data, 0, data.Length);
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2(data, "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate signature and get the validation result
PdfSignatureValidationResult result = signatureField.ValidateSignature(collection);
//Checks whether the signature is valid or not
SignatureStatus status = result.SignatureStatus;
//Checks whether the document is modified or not
bool isModified = result.IsDocumentModified;
//Signature details
string issuerName = signatureField.Signature.Certificate.IssuerName;
DateTime validFrom = signatureField.Signature.Certificate.ValidFrom;
DateTime validTo = signatureField.Signature.Certificate.ValidTo;
string signatureAlgorithm = result.SignatureAlgorithm;
DigestAlgorithm digestAlgorithm = result.DigestAlgorithm;
//Revocation validation details
RevocationResult revocationDetails = result.RevocationResult;
RevocationStatus revocationStatus = revocationDetails.OcspRevocationStatus;
bool isRevokedCRL = revocationDetails.IsRevokedCRL;
//Close the document
loadedDocument.Close(true);//Get the stream from the document
FileStream documentStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//Get signature field
PdfLoadedSignatureField signatureField = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
byte[] data = new byte[certificateStream.Length];
certificateStream.Read(data, 0, data.Length);
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2(data, "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate signature and get the validation result
PdfSignatureValidationResult result = signatureField.ValidateSignature(collection);
//Checks whether the signature is valid or not
SignatureStatus status = result.SignatureStatus;
//Checks whether the document is modified or not
bool isModified = result.IsDocumentModified;
//Signature details
string issuerName = signatureField.Signature.Certificate.IssuerName;
DateTime validFrom = signatureField.Signature.Certificate.ValidFrom;
DateTime validTo = signatureField.Signature.Certificate.ValidTo;
string signatureAlgorithm = result.SignatureAlgorithm;
DigestAlgorithm digestAlgorithm = result.DigestAlgorithm;
//Revocation validation details
RevocationResult revocationDetails = result.RevocationResult;
RevocationStatus revocationStatus = revocationDetails.OcspRevocationStatus;
bool isRevokedCRL = revocationDetails.IsRevokedCRL;
//Close the document
loadedDocument.Close(true);//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf");
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//Get signature field
PdfLoadedSignatureField signatureField = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
byte[] data = new byte[certificateStream.Length];
certificateStream.Read(data, 0, data.Length);
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2(data, "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate signature and get the validation result
PdfSignatureValidationResult result = signatureField.ValidateSignature(collection);
//Checks whether the signature is valid or not
SignatureStatus status = result.SignatureStatus;
//Checks whether the document is modified or not
bool isModified = result.IsDocumentModified;
//Signature details
string issuerName = signatureField.Signature.Certificate.IssuerName;
DateTime validFrom = signatureField.Signature.Certificate.ValidFrom;
DateTime validTo = signatureField.Signature.Certificate.ValidTo;
string signatureAlgorithm = result.SignatureAlgorithm;
DigestAlgorithm digestAlgorithm = result.DigestAlgorithm;
//Revocation validation details
RevocationResult revocationDetails = result.RevocationResult;
RevocationStatus revocationStatus = revocationDetails.OcspRevocationStatus;
bool isRevokedCRL = revocationDetails.IsRevokedCRL;
//Close the document
loadedDocument.Close(true);Validate all signatures in PDF document
Added the support to validate all the digital signatures in an existing PDF document.
You can use the ValidateSignatures method available in the PdfLoadedFormFieldCollection class to validate all the digital signatures. You can get the list of PdfSignatureValidationResult from the ValidateSignatures method.
The following code example explains how to validate all the signatures in digitally signed PDF document.
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2("PDF.pfx", "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate all signatures in loaded PDF document and get the list of validation result
List<PdfSignatureValidationResult> results;
bool isValid = loadedDocument.Form.Fields.ValidateSignatures(collection, out results);
//Close the document
loadedDocument.Close(true);'Load an existing signed PDF document
Dim loadedDocument As PdfLoadedDocument = New PdfLoadedDocument("Input.pdf")
'X509Certificate2Collection to check the signer's identity using root certificates
Dim collection As X509CertificateCollection = New X509CertificateCollection()
'Create new X509Certificate2 with the root certificate
Dim certificate As X509Certificate2 = New X509Certificate2("PDF.pfx", "syncfusion")
'Add the certificate to the collection
collection.Add(certificate)
'Validate all signatures in loaded PDF document and get the list of validation result
Dim results As List<PdfSignatureValidationResult>
Dim isValid As Boolean = loadedDocument.Form.Fields.ValidateSignatures(collection, out results)
'Close the document
loadedDocument.Close(true)//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.Input.pdf");
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.PDF.pfx");
byte[] data = new byte[certificateStream.Length];
certificateStream.Read(data, 0, data.Length);
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2(data, "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate all signatures in loaded PDF document and get the list of validation result
List<PdfSignatureValidationResult> results;
bool isValid = loadedDocument.Form.Fields.ValidateSignatures(collection, out results);
//Close the document
loadedDocument.Close(true);//Get the stream from the document
FileStream documentStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Creates a certificate instance from PFX file with private key
FileStream certificateStream = new FileStream("PDF.pfx", FileMode.Open, FileAccess.Read);
byte[] data = new byte[certificateStream.Length];
certificateStream.Read(data, 0, data.Length);
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2(data, "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate all signatures in loaded PDF document and get the list of validation result
List<PdfSignatureValidationResult> results;
bool isValid = loadedDocument.Form.Fields.ValidateSignatures(collection, out results);
//Close the document
loadedDocument.Close(true);//Get the stream from the document
Stream documentStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf");
//Load an existing signed PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(documentStream);
//X509Certificate2Collection to check the signer's identity using root certificates
X509CertificateCollection collection = new X509CertificateCollection();
//Creates a certificate instance from PFX file with private key
Stream certificateStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.PDF.pfx");
byte[] data = new byte[certificateStream.Length];
certificateStream.Read(data, 0, data.Length);
//Create new X509Certificate2 with the root certificate
X509Certificate2 certificate = new X509Certificate2(data, "syncfusion");
//Add the certificate to the collection
collection.Add(certificate);
//Validate all signatures in loaded PDF document and get the list of validation result
List<PdfSignatureValidationResult> results;
bool isValid = loadedDocument.Form.Fields.ValidateSignatures(collection, out results);
//Close the document
loadedDocument.Close(true);
Was this page helpful?
Yes
No
Thank you for your feedback!
Thank you for your feedback and comments. We will rectify this as soon as possible!
An unknown error has occurred. Please try again.
Help us improve this page