PDF bookmarks

Intro

Some PDF documents can contain the TOC (table of contents) to simplify navigation within the PDF file and to allow structured content representation. It's the thing you usually see then you click on Bookmarks tab in Acrobat Reader. So this table of contents is usually being created by using bookmark objects (this is the PDF name for such objects as defined in specification). This object supports navigation as well as link (see our older posts: working with build-in navigation and how to work with links in PDF documents) being a bit different.

While the samples listed above provide code and theory for highlighting search results or link targets on PDF page, current sample is designed to show the bookmark basics for the most common task – enumerate bookmarks list and show doc's table of contents.

The code

C# code sample below demonstrates how it could be done using our API.

/// <summary>

/// Demonstrates bookmarks enumeration in PDF file.

/// </summary>

class Program

{

    static void Main(string[] args)

    {

       // open and load the file

       using (FileStream fs = new FileStream(@"..\..\..\Documents\development guide.pdf",                FileMode.Open))

       {

           // this object represents a PDF document

           using(Document document = new Document(fs))

           {

               EnumerateBookmarksAndPrint(document.Bookmarks);

           }

       }

       Console.ReadLine();

     }

     /// <summary>

     /// Enumerates the bookmarks and prints their title.

     /// </summary>

     /// <param name="bookmark">The bookmark.</param>

     private static void EnumerateBookmarksAndPrint(Bookmark bookmark)

     {

         if(bookmark!=null)

         {

             Console.WriteLine(bookmark.Title);

             for(int i=0;i<bookmark.Children.Count;i++)

             {

                 EnumerateBookmarksAndPrint(bookmark.Children[i]);

             }

         }

     }

}

Output

1. Introduction

2. Getting started

2.1 Development environment

2.2 Deployment & installation

2.3 Licensing process

2.3.1 Using custom assembly attribute

2.3.2 Applying license manually

3. Product description

3.1 PDF versions supported

3.2. Features and limitations

3.3. Output formats

3.4 Processing highlights

4. Code samples

4.1. Convert PDF document to Bitmap

4.2. Convert PDF to TIFF

4.3. Viewing information about PDF document

4.4. Extracting font information from PDF files

4.5 Advanced conversion using rendering settings

The sample can be found in our download package and is located in Samples\BookmarksUsage folder.

It's also possible to highlight bookmark's destinaton and save desired PDF page to image using the API provided by Apitron PDF Rasterizer for .NET.