更改其他PDF文檔的鏈接

Question

我們有大量的pdf文件，每個文件都有打開其他pdf文件的鏈接。 單擊鏈接時，它將在同一文件系統中打開其他pdf文檔。 問題是我們需要更改某些目錄的名稱，這將需要更改指向該目錄中pdf文檔的所有鏈接。 我們將手動執行此操作，但實際上有數千個鏈接需要更改。

我們試圖使用iTextSharp和PdfSharp來更改鏈接，但是很難找到正確的對象。 下面顯示了帶有兩個鏈接的示例pdf文件的內容。 您可以看到對象12是引用對象21的鏈接，而對象21使用對象20中的引用打開了一個新窗口。對象類型為Filespec的對象20包含鏈接的pdf的路徑Folder-Name / A.pdf。 第二個鏈接遵循相同的模式，但使用對象16、23和22。

12 0 obj<</Type/Annot/P 5 0 R/F 4/C[1 0 0]/Subtype/Link/A 21 0 R/M(D:20130710103035-07'00')/Border[0 0 0]/Rect[144 612 216 630]/NM(QVDTKWKAZGVAAGHJ)/BS 13 0 R>>
endobj
13 0 obj<</W 0/S/S/Type/Border>>
endobj
16 0 obj<</Type/Annot/P 5 0 R/F 4/C[1 0 0]/Subtype/Link/A 23 0 R/M(D:20130710103040-07'00')/Border[0 0 0]/Rect[126 594 216 612]/NM(WFAYQFGTTIESQOKW)/BS 17 0 R>>
endobj
17 0 obj<</W 0/S/S/Type/Border>>
endobj
20 0 obj<</Type/Filespec/F(Folder-Name/A.pdf)/UF(Folder-Name/A.pdf)/Desc()>>
endobj
21 0 obj<</S/GoToR/D[0/Fit]/NewWindow true/F 20 0 R>>
endobj
22 0 obj<</Type/Filespec/F(Folder-Name-2/B.pdf)/UF(Folder-Name-2/B.pdf)/Desc()>>
endobj
23 0 obj<</S/GoToR/D[0/Fit]/NewWindow true/F 22 0 R>>
endobj

我們如何使用iTextSharp或PdfSharp將“文件夾名稱”和“文件夾名稱-2”更改為其他任意文件夾路徑？

Answer 1

萬一有人在意，我可以使用Chris Haas在上面的第一條評論中鏈接的代碼，但對其進行了如下修改：

foreach (FileInfo file in files)
{                    

    PdfReader reader = default(PdfReader);

    bool linkReplaced = false;

    //Setup some variables to be used later
    reader = new PdfReader(file.FullName);

    int pageCount = reader.NumberOfPages;
    PdfDictionary pageDictionary = default(PdfDictionary);
    PdfArray annots = default(PdfArray);

    //Loop through each page
    for (int i = 1; i <= pageCount; i++)
    {
        //Get the current page
        pageDictionary = reader.GetPageN(i);

        //Get all of the annotations for the current page
        annots = pageDictionary.GetAsArray(PdfName.ANNOTS);

        //Make sure we have something
        if ((annots == null) || (annots.Length == 0))
            continue;

        foreach (PdfObject A in annots.ArrayList)
        {
            //Convert the itext-specific object as a generic PDF object
            PdfDictionary AnnotationDictionary = (PdfDictionary)PdfReader.GetPdfObject(A);

            //Make sure this annotation has a link
            if (!AnnotationDictionary.Get(PdfName.SUBTYPE).Equals(PdfName.LINK))
                continue;

            //Make sure this annotation has an ACTION
            if (AnnotationDictionary.Get(PdfName.A) == null)
                continue;

            string fValue = string.Empty;
            string ufValue = string.Empty;
            string uriValue = string.Empty;

            PdfObject a = AnnotationDictionary.Get(PdfName.A);
            if (a.IsDictionary())
            {
                //Get the ACTION for the current annotation
                PdfDictionary AnnotationAction = (PdfDictionary)a;

                //Test if it is a URI action
                if (AnnotationAction.Get(PdfName.S).Equals(PdfName.URI))
                {
                    uriValue = AnnotationAction.Get(PdfName.URI).ToString();

                    if ((uriValue.IndexOf(findValue, StringComparison.OrdinalIgnoreCase) > -1))
                    {
                        string uriValueReplace = Replace(uriValue, findValue, replaceValue, StringComparison.OrdinalIgnoreCase);

                        //Change the URI to something else
                        AnnotationAction.Put(PdfName.URI, new PdfString(uriValueReplace));                                          
                        linkReplaced = true;
                    }
                }                                               
            }
            else if (a.IsIndirect())
            {
                // Get the indirect reference
                PdfIndirectReference indirectRef = (PdfIndirectReference)a;

                // Get the GoToR type object which is at the document level
                PdfDictionary goToR = (PdfDictionary)reader.GetPdfObject(indirectRef.Number);

                // Get the FileSpec object whic his at the document lelvel
                PdfObject f = goToR.Get(PdfName.F);

                if (f == null || !f.IsIndirect())
                    continue;

                PdfObject fileSpecObject = reader.GetPdfObject(((PdfIndirectReference)goToR.Get(PdfName.F)).Number);

                if (!fileSpecObject.IsDictionary())
                    continue;

                PdfDictionary fileSpec = (PdfDictionary)fileSpecObject;

                fValue = fileSpec.Get(PdfName.F).ToString();
                ufValue = fileSpec.Get(PdfName.UF).ToString();

                if ((fValue.IndexOf(findValue, StringComparison.OrdinalIgnoreCase) > -1) || (ufValue.IndexOf(findValue, StringComparison.OrdinalIgnoreCase) > -1))
                {
                    string fValueReplace = Replace(fValue, findValue, replaceValue, StringComparison.OrdinalIgnoreCase);// fValue.Replace(findValue, replaceValue);
                    string ufValueReplace = Replace(fValue, findValue, replaceValue, StringComparison.OrdinalIgnoreCase);// ufValue.Replace(findValue, replaceValue);

                    // Update the references to the file
                    fileSpec.Put(PdfName.F, new PdfString(fValueReplace));
                    fileSpec.Put(PdfName.UF, new PdfString(ufValueReplace));                                    

                    linkReplaced = true;
                }
            }                                
        }
    }
}