Editing Hyperlink and Anchors in PDF using ITextSharp

Question

I am using iTextSharp library and C#.Net for splitting my PDF file.

Consider a PDF file named sample.pdf containing 72 pages. This sample.pdf contains pages that hav

Answer 1

This function below uses iTextSharp to:

1. Open the PDF
2. Page throught he PDF
3. Inspect the annotations on each page for those that are ANCHORS

Step #4 is to insert whatever logic you want in here... update the links, log them, etc.

    /// 
Inspects PDF files for internal links.
    /// 
    public static void FindPdfDocsWithInternalLinks()
    {
        foreach (var fi in PdfFiles) {
            try {
                var reader = new PdfReader(fi.FullName);
                // Pagination
                for(var i = 1; i <= reader.NumberOfPages; i++) {
                    var pageDict = reader.GetPageN(i);
                    var annotArray = (PdfArray)PdfReader.GetPdfObject(pageDict.Get(PdfName.ANNOTS));
                    if (annotArray == null) continue;
                    if (annotArray.Length <= 0) continue;
                    // check every annotation on the page
                    foreach (var annot in annotArray.ArrayList) {
                        var annotDict = (PdfDictionary)PdfReader.GetPdfObject(annot);
                        if (annotDict == null) continue;
                        var subtype = annotDict.Get(PdfName.SUBTYPE).ToString();
                        if (subtype != "/Link") continue;
                        var linkDict = (PdfDictionary)annotDict.GetDirectObject(PdfName.A);
                        if (linkDict == null) continue;
                        // if it makes it this far, its an Anchor annotation
                        // so we can grab it's URI
                        var sUri = linkDict.Get(PdfName.URI).ToString();
                        if (String.IsNullOrEmpty(sUri)) continue;
                    }
                }
                reader.Close();
            }
            catch (InvalidPdfException e)
            {
                if (!fi.FullName.Contains("_vti_cnf"))
                    Console.WriteLine("\r\nInvalid PDF Exception\r\nFilename: " + fi.FullName + "\r\nException:\r\n" + e);
                continue;
            }
            catch (NullReferenceException e) 
            {
                if (!fi.FullName.Contains("_vti_cnf"))
                    Console.WriteLine("\r\nNull Reference Exception\r\nFilename: " + fi.Name + "\r\nException:\r\n" + e);
                continue;
            }
        }

        // DO WHATEVER YOU WANT HERE
    }

Good luck.