Customize Page Numbes While Adding TOC

In this tutoria, we will explore how to customize page numbers while adding a table of contents (TOC) using Aspose.PDF for .NET. We will provide step-by-step guidance, along with a code example, to help you achieve this.

Step 1: Loading an existing PDF file

First, we need to load an existing PDF file. For this tutorial, we will use the file “42824.pdf” located in the “YOUR DOCUMENT DIRECTORY” directory. Replace this directory path with the actual path to your document directory.

string dataDir = "YOUR DOCUMENT DIRECTORY";
string inFile = dataDir + "42824.pdf";
string outFile = dataDir + "42824_out.pdf";
Document doc = new Document(inFile);

Step 2: Adding a TOC page

Next, we need to add a new page at the beginning of the document to serve as the TOC page. We can achieve this by using the Insert() method of the Pages collection of the Document object.

Aspose.Pdf.Page tocPage = doc.Pages.Insert(1);

Step 3: Creating a TOC object

To create a TOC object, we first need to create a TocInfo object and set its properties. In this tutorial, we will set the title of the TOC to “Table Of Contents” and the page number prefix to “P”.

TocInfo tocInfo = new TocInfo();
TextFragment title = new TextFragment("Table Of Contents");
title.TextState.FontSize = 20;
title.TextState.FontStyle = FontStyles.Bold;
tocInfo.Title = title;
tocInfo.PageNumbersPrefix = "P";
tocPage.TocInfo = tocInfo;

Step 4: Creating TOC entries

To create TOC entries, we need to loop through all the pages of the document, except for the TOC page, and create a heading object for each page. We can then add the heading object to the TOC page and specify its destination page.

for (int i = 1; i < doc.Pages.Count; i++)
{
    // Create Heading object
    Aspose.Pdf.Heading heading2 = new Aspose.Pdf.Heading(1);
    TextSegment segment2 = new TextSegment();
    heading2.TocPage = tocPage;
    heading2.Segments.Add(segment2);
    // Specify the destination page for heading object
    heading2.DestinationPage = doc.Pages[i + 1];
    // Destination page
    heading2.Top = doc.Pages[i + 1].Rect.Height;
    // Destination coordinate
    segment2.Text = "Page " + i.ToString();
    // Add heading to page containing TOC
    tocPage.Paragraphs.Add(heading2);
}

Step 5: Saving the updated document

Finally, we need to save the updated document to a new file. We can achieve this by using the Save() method of the Document object.

doc.Save(outFile);

Example source code for customizing page numbes while adding TOC using Aspose.PDF for .NET

string dataDir = "YOUR DOCUMENT DIRECTORY";
string inFile = dataDir + "42824.pdf";
string outFile = dataDir + "42824_out.pdf";
// Load an existing PDF files
Document doc = new Document(inFile);
// Get access to first page of PDF file
Aspose.Pdf.Page tocPage = doc.Pages.Insert(1);
// Create object to represent TOC information
TocInfo tocInfo = new TocInfo();
TextFragment title = new TextFragment("Table Of Contents");
title.TextState.FontSize = 20;
title.TextState.FontStyle = FontStyles.Bold;
// Set the title for TOC
tocInfo.Title = title;
tocInfo.PageNumbersPrefix = "P";
tocPage.TocInfo = tocInfo;
for (int i = 1; i<doc.Pages.Count; i++)
{
	// Create Heading object
	Aspose.Pdf.Heading heading2 = new Aspose.Pdf.Heading(1);
	TextSegment segment2 = new TextSegment();
	heading2.TocPage = tocPage;
	heading2.Segments.Add(segment2);
	// Specify the destination page for heading object
	heading2.DestinationPage = doc.Pages[i + 1];
	// Destination page
	heading2.Top = doc.Pages[i + 1].Rect.Height;
	// Destination coordinate
	segment2.Text = "Page " + i.ToString();
	// Add heading to page containing TOC
	tocPage.Paragraphs.Add(heading2);
}

// Save the updated document
doc.Save(outFile);

Conclusion

In this tutorial, we have provided step-by-step guidance on how to customize page numbers while adding a TOC using Aspose.PDF for .NET. We have also provided a code example that you can use as a reference when implementing this feature in your

FAQ’s

Q: What is a table of contents (TOC) in a PDF document?

A: A table of contents (TOC) in a PDF document is a navigational aid that provides an organized list of document sections or chapters along with their corresponding page numbers. It allows readers to quickly navigate to specific sections within the document.

Q:Why would I want to customize page numbers in a TOC?

A: Customizing page numbers in a TOC can be useful when you want to use a specific page numbering format or include additional information along with the page numbers. It allows you to create a more personalized and informative table of contents.

Q: Can I include hyperlinks in the TOC to link to specific sections or pages within the PDF document?

A: Yes, Aspose.PDF for .NET allows you to create hyperlinks in the TOC that link to specific sections or pages within the PDF document. This enhances the interactivity and navigation of the PDF document.

Q: Is Aspose.PDF for .NET compatible with PDF/A standards?

A: Yes, Aspose.PDF for .NET supports PDF/A standards, including PDF/A-1, PDF/A-2, and PDF/A-3. It allows you to create PDF documents that comply with archiving and long-term preservation requirements.

Q: Can I add more formatting to the TOC entries, such as font styles or colors?

A: Yes, you can add additional formatting to the TOC entries, such as font styles, colors, and font sizes, using Aspose.PDF for .NET. This allows you to customize the appearance of the TOC as per your requirements.