Merge Multiple PDFs

The following example illustrates how to merge two multi-page PDF documents into one document:

C#	Copy Code
using ImageGear.Formats.PDF; // Merges two PDF document into a third PDF document. ImGearPDFDocument MergePdfDocuments(ImGearPDFDocument igFirstDocument, ImGearPDFDocument igSecondDocument) { // ImageGear uses zero-based numeration of pages in document. int FIRST_PAGE_INDEX = 0; // Create new PDF document for result. ImGearPDFDocument igResultDocument = new ImGearPDFDocument(); // Copy all pages of first document into result document. for (int pageIndex = FIRST_PAGE_INDEX; pageIndex < igFirstDocument.Pages.Count; pageIndex++) igResultDocument.Pages.Add(igFirstDocument.Pages[pageIndex].Clone()); // Copy all pages of second document into result document. for (int pageIndex = FIRST_PAGE_INDEX; pageIndex < igSecondDocument.Pages.Count; pageIndex++) igResultDocument.Pages.Add(igSecondDocument.Pages[pageIndex].Clone()); return igResultDocument; }

Copy Code

using ImageGear.Formats.PDF;
       // Merges two PDF document into a third PDF document.
       ImGearPDFDocument MergePdfDocuments(ImGearPDFDocument igFirstDocument, ImGearPDFDocument igSecondDocument)
       {
           // ImageGear uses zero-based numeration of pages in document.
           int FIRST_PAGE_INDEX = 0;

           // Create new PDF document for result.
           ImGearPDFDocument igResultDocument = new ImGearPDFDocument();

           // Copy all pages of first document into result document.
           for (int pageIndex = FIRST_PAGE_INDEX; pageIndex < igFirstDocument.Pages.Count; pageIndex++)
               igResultDocument.Pages.Add(igFirstDocument.Pages[pageIndex].Clone());

           // Copy all pages of second document into result document.
           for (int pageIndex = FIRST_PAGE_INDEX; pageIndex < igSecondDocument.Pages.Count; pageIndex++)
               igResultDocument.Pages.Add(igSecondDocument.Pages[pageIndex].Clone());
           return igResultDocument;
       }

VB.NET	Copy Code
Imports ImageGear.Formats.PDF ' Merges two PDF document into third PDF document. Private Function MergePdfDocuments(igFirstDocument As ImGearPDFDocument, igSecondDocument As ImGearPDFDocument) As ImGearPDFDocument ' ImageGear uses zero-based numeration of pages in document. Dim FIRST_PAGE_INDEX As Integer FIRST_PAGE_INDEX = 0 ' Create new PDF document for result. Dim igResultDocument As New ImGearPDFDocument() ' Copy all pages of first document into result document. Dim pageIndex As Integer = FIRST_PAGE_INDEX While pageIndex < igFirstDocument.Pages.Count igResultDocument.Pages.Add(igFirstDocument.Pages(pageIndex).Clone()) System.Math.Max(System.Threading.Interlocked.Increment(pageIndex), pageIndex - 1) End While ' Copy all pages of second document into result document. pageIndex = FIRST_PAGE_INDEX While pageIndex < igSecondDocument.Pages.Count igResultDocument.Pages.Add(igSecondDocument.Pages(pageIndex).Clone()) System.Math.Max(System.Threading.Interlocked.Increment(pageIndex), pageIndex - 1) End While Return igResultDocument End Function

VB.NET

Copy Code

Imports ImageGear.Formats.PDF
' Merges two PDF document into third PDF document.
Private Function MergePdfDocuments(igFirstDocument As ImGearPDFDocument, igSecondDocument As ImGearPDFDocument) As ImGearPDFDocument

   ' ImageGear uses zero-based numeration of pages in document.
   Dim FIRST_PAGE_INDEX As Integer
   FIRST_PAGE_INDEX = 0

   ' Create new PDF document for result.
   Dim igResultDocument As New ImGearPDFDocument()

   ' Copy all pages of first document into result document.
    Dim pageIndex As Integer = FIRST_PAGE_INDEX
    While pageIndex < igFirstDocument.Pages.Count
       igResultDocument.Pages.Add(igFirstDocument.Pages(pageIndex).Clone())
       System.Math.Max(System.Threading.Interlocked.Increment(pageIndex), pageIndex - 1)
    End While

    ' Copy all pages of second document into result document.
    pageIndex = FIRST_PAGE_INDEX
    While pageIndex < igSecondDocument.Pages.Count
       igResultDocument.Pages.Add(igSecondDocument.Pages(pageIndex).Clone())
       System.Math.Max(System.Threading.Interlocked.Increment(pageIndex), pageIndex - 1)
    End While

    Return igResultDocument

End Function

This method can be extended for any document type. The main rule that must be observed for copying pages from one document to another is that the type of the documents must be the same.