Save PDF file in C# and VB.NET

25 Jul 202610 minutes to read

Namespaces required

The following namespace of the Essential® PDF library must be included in your application to save a PDF document.

using Syncfusion.Pdf.Parsing;
using Syncfusion.Pdf.Parsing;
Imports Syncfusion.Pdf.Parsing

Saving a PDF document to the file system

You can save the manipulated PDF document to the file system using the Save method of the PdfLoadedDocument class.

//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Save the document to the file system.
loadedDocument.Save("Output.pdf");
//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Save the document to the file system.
loadedDocument.Save("Output.pdf");
'Load an existing PDF document.
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'To-Do some manipulation
'Save the document to the file system.
loadedDocument.Save("Output.pdf")

Saving a PDF document to a stream

You can also save the manipulated PDF document to a stream using the overloads of the Save method.

//Load an existing PDF document.
FileStream docStream = new FileStream("Input.pdf", FileMode.Open, FileAccess.Read);
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(docStream);
//To-Do some manipulation
//Save the document into stream.
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Creates an instance of memory stream.
MemoryStream stream = new MemoryStream();
//Save the document stream.
loadedDocument.Save(stream);
'Load an existing PDF document.
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'To-Do some manipulation
'Creates an instance of memory stream.
Dim stream As New MemoryStream()
'Save the document to stream.
loadedDocument.Save(stream)

Saving a PDF document into the same file or stream

You can also resave the manipulated PDF document to the same file using the overloads of the Save method.

//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Resave the document to the same file.
loadedDocument.Save();
//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Resave the document to the same file.
loadedDocument.Save();
'Load an existing PDF document.
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'To-Do some manipulation
'Resave the document to the same file.
loadedDocument.Save()
//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(stream);
//To-Do some manipulation
//Resave the document to the same stream.
loadedDocument.Save();
//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument(stream);
//To-Do some manipulation
//Resave the document to the same stream.
loadedDocument.Save();
'Load an existing PDF document.
Dim loadedDocument As New PdfLoadedDocument(stream)
'To-Do some manipulation
'Resave the document to the same stream.
loadedDocument.Save()

Closing a document

After the document manipulation and save operations are completed, you should close the instance of PdfLoadedDocument to release all the memory consumed by the PDF DOM. The following code snippet illustrates how to Close a PdfLoadedDocument instance.

//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Save the document into stream.
MemoryStream stream = new MemoryStream();
loadedDocument.Save(stream);
//Close the document.
loadedDocument.Close(true);
//Load an existing PDF document.
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Input.pdf");
//To-Do some manipulation
//Save the document to the file system.
loadedDocument.Save("Output.pdf");
//Close the document.
loadedDocument.Close(true);
'Load an existing PDF document.
Dim loadedDocument As New PdfLoadedDocument("Input.pdf")
'To-Do some manipulation
'Save the document to the file system.
loadedDocument.Save("Output.pdf")
'Close the document.
loadedDocument.Close(True)

NOTE

  1. The Close() method disposes all the memory consumed by the PDF DOM.
  2. The Close(true) method disposes all the memory consumed by the PDF DOM and also disposes the underlying document stream.
  3. Always call Close() (or wrap the document in a using block) to prevent memory leaks and locked file handles.

Secured document exception

You can catch the exception thrown when opening an existing encrypted PDF document from the file system, a stream, or a byte array using the following code samples.

//Load an existing PDF document.
PdfLoadedDocument document = null;
try
{
    //Open an existing PDF document from a stream.
    document = new PdfLoadedDocument("Input.pdf", "password");
}
catch (Syncfusion.Pdf.PdfInvalidPasswordException exception)
{
    //Secured PDF document password is invalid or opened without a password.
}
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Close the document.
document.Close(true);
PdfLoadedDocument document = null;
try
{
    //Load an existing PDF document.
    document = new PdfLoadedDocument("Input.pdf", "password");
}
catch (Syncfusion.Pdf.PdfInvalidPasswordException exception)
{
    //The secured PDF document password is invalid or the document was opened without a password.
}
//Save the document.
document.Save("Output.pdf");
//Close the document.
document.Close(true);
Dim document As PdfLoadedDocument = Nothing
Try
  'Load an existing PDF document.
  document = New PdfLoadedDocument("Input.pdf", "password")
Catch exception As Syncfusion.Pdf.PdfInvalidPasswordException
  'The secured PDF document password is invalid or the document was opened without a password.
End Try
'Save the document.
document.Save("Output.pdf")
'Close the document.
document.Close(True)

Possible error messages of invalid PDF documents while loading

The following are the possible error messages that can occur when loading an invalid PDF document:

I. Corruption errors that cannot be repaired:

  1. Could not find a valid signature (%PDF-).
  2. Bad Format error.
  3. Lexical Error: Unmatched Input.
  4. The document does not contain EOF.
  5. The document has corrupted cross reference tables.
  6. Error: Bad input stream initializer.
  7. Fatal Error occurred.

II. Offset errors that may be repairable (handled by the OpenAndRepair overload):

  1. Invalid cross-reference table with offset position.
  2. Trailer Prev offset is located in the same cross table section.
//Load a PDF document.
PdfLoadedDocument document = null;
try
{
    //Open an existing PDF document from the stream.
    document = new PdfLoadedDocument("Input.pdf", true);
}
catch (PdfException exception)
{
    //Invalid cross-reference table with offset position
    //Trailer Prev offset is located in the same cross table section
    //Could not find a valid signature (%PDF-).
    //Bad Format error
    //Lexical error: Unmatched input
    //The document does not contain EOF
    //The document has corrupted cross reference table
    //Error: Bad input stream initializer
    //Fatal error occured
    //Unexpected token name before 257
}
//Save the document.
MemoryStream stream = new MemoryStream();
document.Save(stream);
//Close the document.
document.Close(true);
PdfLoadedDocument document = null;
try
{
    //Open an existing PDF document from the disk.
    document = new PdfLoadedDocument("Input.pdf", true);
}
catch (Exception exception)
{
    //Invalid cross-reference table with offset position
    //Trailer Prev offset is located in the same cross table section
    //Could not find a valid signature (%PDF-).
    //Bad Format error
    //Lexical error: Unmatched input
    //The document does not contain EOF
    //The document has corrupted cross reference tables
    //Error: Bad input stream initializer
    //Fatal error occurred
}
//Save the document.
document.Save("Output.pdf");
//Close the document.
document.Close(true);
Dim document As PdfLoadedDocument = Nothing
Try
    'Load an existing document.
    document = New PdfLoadedDocument("Input.pdf", true)
Catch exception As Exception
    'Invalid cross-reference table with offset position
    'Trailer Prev offset is located in the same cross table section
    'Could not find a valid signature (%PDF-).
    'Bad Format error
    'Lexical error: Unmatched input
    'The document does not contain EOF
    'The document has corrupted cross reference tables
    'Error: Bad input stream initializer
    'Fatal error occurred
End Try
'Save the document.
document.Save("Output.pdf")
'Close the document.
document.Close(True)