Merge PDF files in .NET MAUI

Overview

The Syncfusion .NET MAUI PDF library makes it easy to merge or combine multiple PDF files into a single PDF document in C#. The process is simple and efficient, and the merged PDF files retain their original formatting, layout, annotations, bookmarks, form fields, and appearance.

Merge PDF documentation

Explore more examples of merge PDF files

.NET MAUI merge PDF

How to merge PDF files in C#

Install Syncfusion.Pdf.Net.Core NuGet package in your project.
Create a PdfDocument object.
Create two FileStream objects to represent the two input PDF files.
Call the PdfDocumentBase.Merge() method to merge the two input PDF files into the PdfDocument object.
Save the PdfDocument object to the MemoryStream object.

Here is an example of how to merge PDF files in C# using the Syncfusion .NET MAUI PDF library. You can merge multiple PDF files into a single PDF document with just a few lines of code.

c#
//Create a PDF document. 
using (PdfDocument finalDocument = new PdfDocument())
{
    //Get the stream from an existing PDF document. 
    using (Stream firstPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File1.pdf"))
    using (Stream secondPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File2.pdf"))
    {
        //Create a PDF stream for merging. 
        Stream[] streams = { firstPDFStream, secondPDFStream };
        //Merge PDF documents.
        PdfDocumentBase.Merge(finalDocument, streams);
        //Save the PDF document to stream.
        using (MemoryStream outputStream = new MemoryStream())
        {
            finalDocument.Save(outputStream);
        }
    }
}

PDF - Merge options

Merge specific range of pages from different PDF documents

Merging specific ranges of pages from different PDF documents is a quick and easy way to combine different parts of documents into a single PDF document.

c#
//Create a PDF document.
using (PdfDocument finalDocument = new PdfDocument())
{
    //Get the stream from an existing PDF document. 
    using (Stream firstPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File1.pdf"))
    {
        //Load the first PDF document. 
        PdfLoadedDocument loadedDocument1 = new PdfLoadedDocument(firstPDFStream);
        //Import a range of pages from the first PDF document into the final document 
        //The range starts at page 2 and ends at the last page. 
        finalDocument.ImportPageRange(loadedDocument1, 1, loadedDocument1.Pages.Count - 1);
        using (Stream secondPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File2.pdf"))
        {
            //Load the second PDF document. 
            PdfLoadedDocument loadedDocument2 = new PdfLoadedDocument(secondPDFStream);
            //Import a range of pages from the second PDF document into the final document.
            //The range starts at page 2 and ends at page 5. 
            finalDocument.ImportPageRange(loadedDocument2, 2, 5);

            //Save the PDF document to stream.
            using (MemoryStream outputStream = new MemoryStream())
            {
            finalDocument.Save(outputStream);
            }
        }
    }
}

Extend margin

Extend the margin of PDF pages while merging PDF documents.

c#
//Create a PDF document 
using (PdfDocument finalDocument = new PdfDocument())
{
    //Get the stream from an existing PDF document. 
    using (Stream firstPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File1.pdf"))
    using (Stream secondPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File2.pdf"))
    {
        //Create a PDF stream for merging. 
        Stream[] streams = { firstPDFStream, secondPDFStream };
        //Create a merge options object. 
        PdfMergeOptions mergeOptions = new PdfMergeOptions();
        //Enable the extend margin option. 
        mergeOptions.ExtendMargin = true;               
        //Merge PDF documents. 
        PdfDocumentBase.Merge(finalDocument, mergeOptions, streams);

        //Save the PDF document to stream.
        using (MemoryStream outputStream = new MemoryStream())
        {
            finalDocument.Save(outputStream);
        }
    }
}

Optimize PDF resources

Optimize PDF resources when merging multiple PDF documents into a single PDF document.

c#
//Create a PDF document.
using (PdfDocument finalDocument = new PdfDocument())
{
    //Get the stream from an existing PDF document. 
    using (Stream firstPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File1.pdf"))
    using (Stream secondPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File2.pdf"))
    {
        //Create a PDF stream for merging. 
        Stream[] streams = { firstPDFStream, secondPDFStream };
        //Create a merge options object. 
        PdfMergeOptions mergeOptions = new PdfMergeOptions();
        //Enable the optimize resources option. 
        mergeOptions.OptimizeResources = true;         
        //Merge PDF documents. 
        PdfDocumentBase.Merge(finalDocument, mergeOptions, streams);

        //Save the PDF document to stream.
        using (MemoryStream outputStream = new MemoryStream())
        {
            finalDocument.Save(outputStream);
        }
    }
}

Add bookmarks to merged PDF documents

When merging multiple PDF files, users can create bookmarks based on the titles of individual files. This will help quickly navigate to specific sections of the merged file.

c#
//Create a PDF document 
using (PdfDocument finalDocument = new PdfDocument())
{
    //Get the stream from an existing PDF document. 
    using (Stream firstPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File1.pdf"))
    using (Stream secondPDFStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("Sample.Resources.File2.pdf"))
    {
        //Create a PDF stream for merging. 
        Stream[] streams = { firstPDFStream, secondPDFStream };                   
        //Merge PDF documents. 
        PdfDocumentBase.Merge(finalDocument, streams);
        //Create a bookmark for the first PDF file. 
        PdfBookmark bookmark1 = finalDocument.Bookmarks.Add("Chapter 1 - Barcodes");
        //Set the destination page for the first bookmark.  
        bookmark1.Destination = new PdfDestination(finalDocument.Pages[0]);
        //Set the destination for the first bookmark.  
        bookmark1.Destination.Location = new PointF(20, 20);
        //Create a bookmark for the second PDF file. 
        PdfBookmark bookmark2 = finalDocument.Bookmarks.Add("Chapter 2 - HTTP Succinctly");
        //Set the destination page for the second bookmark.  
        bookmark2.Destination = new PdfDestination(finalDocument.Pages[3]);
        //Set the destination  for the second bookmark. 
        bookmark2.Destination.Location = new PointF(20, 20);

        //Save the PDF document to stream.
        using (MemoryStream outputStream = new MemoryStream())
        {
            finalDocument.Save(outputStream);
        }
    }
}

Use cases

Merging PDF files using the Syncfusion.NET PDF library is a fast and efficient way to manage multiple PDF documents using C#. Besides this process, developers can also: