Combine two (or more) PDF's

Question

Background: I need to provide a weekly report package for my sales staff. This package contains several (5-10) crystal reports.

Problem:

Answer 1

Here is a example using iTextSharp

public static void MergePdf(Stream outputPdfStream, IEnumerable<string> pdfFilePaths)
{
    using (var document = new Document())
    using (var pdfCopy = new PdfCopy(document, outputPdfStream))
    {
        pdfCopy.CloseStream = false;
        try
        {
            document.Open();
            foreach (var pdfFilePath in pdfFilePaths)
            {
                using (var pdfReader = new PdfReader(pdfFilePath))
                {
                    pdfCopy.AddDocument(pdfReader);
                    pdfReader.Close();
                }
            }
        }
        finally
        {
            document?.Close();
        }
    }
}

The PdfReader constructor has many overloads. It's possible to replace the parameter type IEnumerable<string> with IEnumerable<Stream> and it should work as well. Please notice that the method does not close the OutputStream, it delegates that task to the Stream creator.

Answer 2

I had to solve a similar problem and what I ended up doing was creating a small pdfmerge utility that uses the PDFSharp project which is essentially MIT licensed.

The code is dead simple, I needed a cmdline utility so I have more code dedicated to parsing the arguments than I do for the PDF merging:

using (PdfDocument one = PdfReader.Open("file1.pdf", PdfDocumentOpenMode.Import))
using (PdfDocument two = PdfReader.Open("file2.pdf", PdfDocumentOpenMode.Import))
using (PdfDocument outPdf = new PdfDocument())
{                
    CopyPages(one, outPdf);
    CopyPages(two, outPdf);

    outPdf.Save("file1and2.pdf");
}

void CopyPages(PdfDocument from, PdfDocument to)
{
    for (int i = 0; i < from.PageCount; i++)
    {
        to.AddPage(from.Pages[i]);
    }
}

Answer 3

Here the solution http://www.wacdesigns.com/2008/10/03/merge-pdf-files-using-c It use free open source iTextSharp library http://sourceforge.net/projects/itextsharp

Answer 4

Combining two byte[] using iTextSharp up to version 5.x:

internal static MemoryStream mergePdfs(byte[] pdf1, byte[] pdf2)
{
    MemoryStream outStream = new MemoryStream();
    using (Document document = new Document())
    using (PdfCopy copy = new PdfCopy(document, outStream))
    {
        document.Open();
        copy.AddDocument(new PdfReader(pdf1));
        copy.AddDocument(new PdfReader(pdf2));
    }
    return outStream;
}

Instead of the byte[]'s it's possible to pass also Stream's

Answer 5

Here is a single function that will merge X amount of PDFs using PDFSharp

using PdfSharp;
using PdfSharp.Pdf;
using PdfSharp.Pdf.IO;

public static void MergePDFs(string targetPath, params string[] pdfs) {
    using(PdfDocument targetDoc = new PdfDocument()){
        foreach (string pdf in pdfs) {
            using (PdfDocument pdfDoc = PdfReader.Open(pdf, PdfDocumentOpenMode.Import)) {
                for (int i = 0; i < pdfDoc.PageCount; i++) {
                    targetDoc.AddPage(pdfDoc.Pages[i]);
                }
            }
        }
        targetDoc.Save(targetPath);
    }
}

Answer 6

I combined the two above, because I needed to merge 3 pdfbytes and return a byte

internal static byte[] mergePdfs(byte[] pdf1, byte[] pdf2,byte[] pdf3)
        {
            MemoryStream outStream = new MemoryStream();
            using (Document document = new Document())
            using (PdfCopy copy = new PdfCopy(document, outStream))
            {
                document.Open();
                copy.AddDocument(new PdfReader(pdf1));
                copy.AddDocument(new PdfReader(pdf2));
                copy.AddDocument(new PdfReader(pdf3));
            }
            return outStream.ToArray();
        }