Working with Attachments

4 Jan 202316 minutes to read

Essential PDF provides support for file attachments in PDF documents.

Attachments can contain any kind of file with detailed information.

Adding attachment to a PDF document

You can add a text file attachment to a PDF document using PdfAttachment class. The following code example illustrates this.

C#

//Create a new PDF document
PdfDocument document = new PdfDocument();

//Create an attachment
PdfAttachment attachment = new PdfAttachment("Input.txt");
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";
//Adds the attachment to the document
document.Attachments.Add(attachment);

//Save and close the PDF document
document.Save("Output.pdf");
document.Close(true);

VB.NET

'Create a new PDF document
Dim document As New PdfDocument()

'Create an attachment
Dim attachment As New PdfAttachment("Input.txt")
attachment.ModificationDate = DateTime.Now
attachment.Description = "Input.txt"
attachment.MimeType = "application/txt"
'Adds the attachment to the document
document.Attachments.Add(attachment)

'Save and close the PDF document
document.Save("Output.pdf")
document.Close(True)

UWP

//Creates a new PDF document
PdfDocument document = new PdfDocument();

//Load the file as stream
Stream fileStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.Input.txt");
//Creates an attachment
PdfAttachment attachment = new PdfAttachment(@"Input.txt", fileStream);
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";
//Adds the attachment to the document
document.Attachments.Add(attachment);

//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
await document.SaveAsync(memoryStream);
//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(memoryStream, "Output.pdf");

ASP.NET Core

//Create a new PDF document
PdfDocument document = new PdfDocument();

//Creates an attachment
Stream fileStream = new FileStream("Input.txt", FileMode.Open, FileAccess.Read);
PdfAttachment attachment = new PdfAttachment("Input.txt", fileStream);
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";
//Adds the attachment to the document
document.Attachments.Add(attachment);

//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
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);

Xamarin

//Creates a new PDF document
PdfDocument document = new PdfDocument();

//Creates an attachment
Stream fileStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.txt");
PdfAttachment attachment = new PdfAttachment("Input.txt", fileStream);
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";
//Adds the attachment to the document
document.Attachments.Add(attachment);

//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
document.Save(memoryStream);
//Close the document
document.Close(true);
//Save the stream into pdf file
//The operation in SaveAndView under Xamarin varies between Windows Phone, Android and iOS platforms. Please refer 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);
}

You can download a complete working sample from GitHub.

Essential PDF also provides support for adding the attachments to existing PDF documents by using PdfAttachment class. The following code example illustrates the same.

C#

//Load an existing PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");

//Create an attachment
PdfAttachment attachment = new PdfAttachment("Input.txt");
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";

if (loadedDocument.Attachments == null)
    loadedDocument.CreateAttachment();
//Add the attachment to the document
loadedDocument.Attachments.Add(attachment);

//Save and close the PDF document
loadedDocument.Save("Output.pdf");
loadedDocument.Close(true);

VB.NET

'Load an existing PDF document
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")

'Create an attachment
Dim attachment As New PdfAttachment("Input.txt")
attachment.ModificationDate = DateTime.Now
attachment.Description = "Input.txt"
attachment.MimeType = "application/txt"

If loadedDocument.Attachments Is Nothing Then
	loadedDocument.CreateAttachment()
End If
'Add the attachment to the document
loadedDocument.Attachments.Add(attachment)

'Save and close the PDF document
loadedDocument.Save("Output.pdf")
loadedDocument.Close(True)

UWP

//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);

//Load the file as stream
Stream fileStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Data.Input.txt");
//Creates an attachment
PdfAttachment attachment = new PdfAttachment("Input.txt", fileStream);
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";

if (loadedDocument.Attachments == null)
    loadedDocument.CreateAttachment();
//Add the attachment to the document
loadedDocument.Attachments.Add(attachment);

//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
await loadedDocument.SaveAsync(memoryStream);
//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(memoryStream, "Output.pdf");

ASP.NET Core

//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);

//Creates an attachment
Stream fileStream = new FileStream("Input.txt", FileMode.Open, FileAccess.Read);
PdfAttachment attachment = new PdfAttachment("Input.txt", fileStream);
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";

if (loadedDocument.Attachments == null)
    loadedDocument.CreateAttachment();
//Add the attachment to the document
loadedDocument.Attachments.Add(attachment);

//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);

Xamarin

//Load the file as stream
Stream docStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf");
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);

//Creates an attachment
Stream fileStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.txt");
PdfAttachment attachment = new PdfAttachment("Input.txt", fileStream);
attachment.ModificationDate = DateTime.Now;
attachment.Description = "Input.txt";
attachment.MimeType = "application/txt";

if (loadedDocument.Attachments == null)
    loadedDocument.CreateAttachment();
//Add the attachment to the document
loadedDocument.Attachments.Add(attachment);

//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
loadedDocument.Save(memoryStream);
//Close the document
loadedDocument.Close(true);
//Save the stream into pdf file
//The operation in SaveAndView under Xamarin varies between Windows Phone, Android and iOS platforms. Please refer 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);
}

You can download a complete working sample from GitHub.

Removing attachment from an existing PDF

Essential PDF allows you to remove the attachments from the existing document by using Remove and RemoveAt method in PdfAttachment class. The following code example explains the same.

C#

//Loads the PDF document
PdfLoadedDocument document = new PdfLoadedDocument("Input.pdf");

//Removes an attachment
PdfAttachment attachment = document.Attachments[0];
document.Attachments.Remove(attachment);
document.Attachments.RemoveAt(1);

//Save and close the document
document.Save("Output.pdf");
document.Close(true);

VB.NET

'Loads the PDF document
Dim document As New PdfLoadedDocument("Input.pdf")

'Removes an attachments
Dim attachment As PdfAttachment = document.Attachments(0)
document.Attachments.Remove(attachment)
document.Attachments.RemoveAt(1)

'Save and close the document
document.Save("Output.pdf")
document.Close(True)

UWP

//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 document = new PdfLoadedDocument();
//Loads or opens an existing PDF document through Open method of PdfLoadedDocument class
await document.OpenAsync(file);

//Removes an attachment
PdfAttachment attachment = document.Attachments[0];
document.Attachments.Remove(attachment);
document.Attachments.RemoveAt(1);

//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
await document.SaveAsync(memoryStream);
//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(memoryStream, "Output.pdf");

ASP.NET Core

//Load the PDF document
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument document = new PdfLoadedDocument(docStream);

//Removes an attachment
PdfAttachment attachment = document.Attachments[0];
//document.Attachments.Remove(attachment);
document.Attachments.RemoveAt(0);

//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
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);

Xamarin

//Load the file as stream
Stream docStream = typeof(App).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Assets.Input.pdf");
PdfLoadedDocument document = new PdfLoadedDocument(docStream);

//Removes an attachment
PdfAttachment attachment = document.Attachments[0];
document.Attachments.Remove(attachment);
//document.Attachments.RemoveAt(1);

//Save the document into stream
MemoryStream memoryStream = new MemoryStream();
document.Save(memoryStream);
//Close the document
document.Close(true);
//Save the stream into pdf file
//The operation in SaveAndView under Xamarin varies between Windows Phone, Android and iOS platforms. Please refer 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);
}

You can download a complete working sample from GitHub.

Extracting and saving an attachment to the disk.

Essential PDF provides support for extracting the attachments and saving them to the disk. The following code example explains how to extract and save an attachment using PdfAttachment class.

C#

//Loads the PDF document
PdfLoadedDocument document = new PdfLoadedDocument("Sample.pdf");

//Iterates the attachments
foreach (PdfAttachment attachment in document.Attachments)
{
    //Extracts the attachment and saves it to the disk
    FileStream s = new FileStream(attachment.FileName, FileMode.Create);
    s.Write(attachment.Data, 0, attachment.Data.Length);
    s.Dispose();
}

//Save and close the document
document.Save("Output.pdf");
document.Close(true);

VB.NET

'Loads the PDF document
Dim document As New PdfLoadedDocument("Sample.pdf")

'Iterates the attachments
For Each attachment As PdfAttachment In document.Attachments
    'Extracts the attachment and saves it to the disk
    Dim s As New FileStream(attachment.FileName, FileMode.Create)
    s.Write(attachment.Data, 0, attachment.Data.Length)
    s.Dispose()
Next

'Save and close the document
document.Save("Output.pdf")
document.Close(True)

UWP

//PDF supports extracting and saving an attachment to the disk only in Windows Forms, WPF, ASP.NET, ASP.NET MVC and ASP.NET Core platforms.

ASP.NET Core

//Load the PDF document
FileStream docStream = new FileStream("Output.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument document = new PdfLoadedDocument(docStream);

//Iterates the attachments
foreach (PdfAttachment attachment in document.Attachments)
{
    //Extracts the attachment and saves it to the disk
    FileStream s = new FileStream(attachment.FileName, FileMode.Create);
    s.Write(attachment.Data, 0, attachment.Data.Length);
    s.Dispose();
}

//Save the document into stream
MemoryStream stream = new MemoryStream();
document.Save(stream);
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);

Xamarin

//PDF supports extracting and saving an attachment to the disk only in Windows Forms, WPF, ASP.NET, ASP.NET MVC and ASP.NET Core platforms.

You can download a complete working sample from GitHub.