Error: Using operand of type iTextSharp.txt.pdf.PdfStamper must implement System.IDisposable in ASP.Net

Last Reply one month ago By simonoldma

Posted one month ago

Dear friends from ASPFORUMS,

Tried to use the solution from your article published in ASPSNIPPETS "iTextSharp: Add Page numbers to existing PDF using C# and VB.Net

18 Mar 2015  5 Comments 23185 Views
Getting the error: 'Using' operand of type 'iTextSharp.text.pdf.PdfStamper' must implement 'System.IDisposable'.
Please help me,
Simon Mardakh.
Posted one month ago

Hi simonoldma,

Will you please let me know which version of dll you are using.

Posted one month ago

Hi simonoldma,

Change with the below code and check.


protected void AddPageNumber(object sender, EventArgs e)
    byte[] bytes = File.ReadAllBytes(Server.MapPath("~/PDF/Test.pdf"));
    Font blackFont = FontFactory.GetFont("Arial", 12, Font.NORMAL, BaseColor.BLACK);
    using (MemoryStream stream = new MemoryStream())
        PdfReader reader = new PdfReader(bytes);
        PdfStamper stamper = new PdfStamper(reader, stream);
        int pages = reader.NumberOfPages;
        for (int i = 1; i <= pages; i++)
            ColumnText.ShowTextAligned(stamper.GetUnderContent(i), Element.ALIGN_RIGHT, new Phrase(i.ToString(), blackFont), 568f, 15f, 0);
        bytes = stream.ToArray();
    File.WriteAllBytes(Server.MapPath("~/PDF/Test1.pdf"), bytes);


Protected Sub AddPageNumber(sender As Object, e As EventArgs)
    Dim bytes As Byte() = File.ReadAllBytes(Server.MapPath("~/PDF/Test.pdf"))
    Dim blackFont As Font = FontFactory.GetFont("Arial", 12, Font.NORMAL, BaseColor.BLACK)
    Using stream As New MemoryStream()
        Dim reader As New PdfReader(bytes)
        Dim stamper As New PdfStamper(reader, stream)
        Dim pages As Integer = reader.NumberOfPages
        For i As Integer = 1 To pages
            ColumnText.ShowTextAligned(stamper.GetUnderContent(i), Element.ALIGN_RIGHT, New Phrase(i.ToString(), blackFont), 568.0F, 15.0F, 0)
        bytes = stream.ToArray()
    End Using
    File.WriteAllBytes(Server.MapPath("~/PDF/Test1.pdf"), bytes)
End Sub


Posted one month ago

The code worked.  Thank you. Must admit that ASPFORUMS is the best in the world!  Simon M.


Posted one month ago

Not certain which version is.  But as I know it is not too old.  was downloaded in 2016.  I got the help from dharmendr  and do not have problems with code.

I agree, here is the link: