TOC Generator Plugin for Aspose.PDF
How to Add a Table of Contents to a PDF in .NET

How to Add a Table of Contents to a PDF in .NET

This article explains how to programmatically add a Table of Contents (TOC) to a PDF document using Aspose.PDF TOC Generator for .NET. A TOC enhances document navigation, professional appearance, and user experience—ideal for reports, manuals, e-books, and more.

Real-World Problem

Manually creating a TOC in a PDF is tedious, error-prone, and unscalable. Automating TOC generation ensures accuracy and saves time, especially when handling multi-section or large documents in enterprise, academic, or publishing workflows.

Solution Overview

Aspose.PDF TOC Generator for .NET lets you:

  • Add a structured TOC to any PDF document
  • Integrate with .NET (C#, VB.NET) projects for seamless automation
  • Support batch processing for multiple PDFs
  • Customize TOC styles and output file paths

Prerequisites

  • Visual Studio 2019 or later
  • .NET 6.0 or later
  • Aspose.PDF for .NET installed via NuGet
PM> Install-Package Aspose.PDF

Step-by-Step Implementation

Step 1: Install and Configure Aspose.PDF 

using Aspose.Pdf.Plugins;
using System.IO;

Step 2: Add a Table of Contents to a PDF 

var generator = new TocGenerator();
var options = new TocOptions();
options.AddInput(new FileDataSource(@"C:\Samples\sample.pdf"));
options.AddOutput(new FileDataSource(@"C:\Samples\sample_toc.pdf"));
generator.Process(options);

Use Cases & Applications (With Code Variations)

1. Batch Insert TOC into Multiple PDFs 

string[] pdfs = Directory.GetFiles(@"C:\Docs\", "*.pdf");
foreach (var file in pdfs)
{
    var options = new TocOptions();
    options.AddInput(new FileDataSource(file));
    options.AddOutput(new FileDataSource($@"C:\Docs\toc_{Path.GetFileName(file)}"));
    using (var generator = new TocGenerator())
    {
        generator.Process(options);
    }
}

2. Merge Several PDFs and Insert a Unified TOC

  • First merge documents (see Merger article/code), then use TOC Generator on the merged output to create a single, unified TOC covering all sections.

3. Customize TOC Styling (Font, Size, etc.)

  • For advanced styling, extend or post-process the output PDF using other Aspose.PDF features.
  • If the plugin exposes additional style properties in the future, add them to the TocOptions before processing.

Best Practices and Tips

  • Always review the generated TOC for completeness, especially after merging multiple documents.
  • Automate TOC insertion as part of your document publishing pipeline for consistency.
  • For complex structures (multi-level TOCs), consider enhancing bookmarks/metadata in your source PDF before generating the TOC.
  • Test output PDFs across different readers (Adobe, browser, etc.) to ensure navigation is correct.

Complete Implementation Example 

using Aspose.Pdf.Plugins;
using System;
using System.IO;

class Program
{
    static void Main()
    {
        var generator = new TocGenerator();
        var options = new TocOptions();
        options.AddInput(new FileDataSource(@"C:\Samples\sample.pdf"));
        options.AddOutput(new FileDataSource(@"C:\Samples\sample_toc.pdf"));
        generator.Process(options);
        Console.WriteLine("TOC added successfully!");
    }
}

Conclusion

Aspose.PDF TOC Generator for .NET is the fastest way to enhance PDF navigation and professionalism with a dynamic Table of Contents. Whether for single documents, batches, or combined files, you can automate TOC creation, streamline large publishing tasks, and deliver a better experience to your end users.

 English