We're sorry Aspose doesn't work properply without JavaScript enabled.

Free Support Forum - aspose.com

PDFFileEditor.Concatenate - Cannot Access a Closed Stream

I am currently having an issue using the Aspose.Pdf.Kit.PdfFileEditor.Concatenate function.

I am using it to concatenate streams into a final document. The function returns True, so I believe it is working, however, the output stream is returned in a closed state.

I tried using the following overloads with the same result:

  • Concatenate(System.IO.Stream(), System.IO.Stream)
  • Concatenate(System.IO.Stream, System.IO.Stream, System.IO.Stream)

Here is some sample code that reproduces the issue (this code is referencing version of the Aspose.Pdf.Kit.dll file)

        Dim inFile1 As String = "c:\example1.pdf"
        Dim inFile2 As String = "c:\example2.pdf"
        Dim outFile As String = "c:\out.pdf"
        Dim inStream1 As FileStream = New FileStream(inFile1, FileMode.Open)
        Dim inStream2 As fileStream = New FileStream(inFile2, FileMode.Open)
        Dim outputStream As FileStream = New FileStream(outFile, FileMode.Create)
        Dim innerStream As MemoryStream = New MemoryStream()
    'Concatnate input Pdf file1 and file2, output is saved in innerStream.
    Dim editor As PdfFileEditor = New PdfFileEditor()
    Dim bReturn As Boolean

    bReturn = editor.Concatenate(inStream1, inStream2, innerStream)
    Debug.WriteLine("bReturn = " & bReturn)
    Debug.WriteLine("Is Stream Closed? " & Not innerStream.CanRead())
        'At This point, innerStream is closed, and will throw an exception if accessed.
        Debug.Print("Stream Size: " & innerStream.Length)
    Catch ex As Exception
    End Try

    innerStream.Close()</PRE><PRE> </PRE>The Output is: <PRE>bReturn = True

Is Stream Closed? True
A first chance exception of type ‘System.ObjectDisposedException’ occurred in mscorlib.dll
Cannot access a closed Stream.

Thanks for your assistance.


Hi Brad,

Please download the hot fix for this issue from this link. Please note that when using this hot fix, you’ll also have to set the position of all the input memory streams to 0 i.e. inStream1.Position = 0.

I hope this resolves your issue. If you still find any problem or have some more questions, please do let us know.

We’re sorry for the inconvenience.