Highlight PDF Document with C# REST API

This tutorial guides how to highlight PDF document with C# REST API. You will learn to develop a PDF highlighter with C# RESTful Service using a .NET-based Could SDK. All the details are available to customize the highlighting by setting various parameters.

Prerequisite

Steps to Highlight Text in PDF Document with C# Low Code API

  1. Configure the PdfApi class object by providing the API key and application SID for highlighting the text
  2. Create a HighlightAnnotation object by setting the rectangular area and color
  3. Set the creation and modified date of the annotation
  4. Upload the target PDF file to a Cloud storage for highlighting the text
  5. Call the PostPageHighlightAnnotations() method by setting the input file, page number, and annotations
  6. Download the PDF file after highlighting

These steps describe how to highlight in a PDF with C# Low Code API. Create a PdfApi object, instantiate a HighlightAnnotation by setting the rectangular area with color, modification, and creation date, and upload the PDF file to the Cloud storage. Finally, call the PostPageHighlightAnnotations() method to highlight the area around the target contents.

Code to Highlight Text in PDF with C# REST Interface

This code demonstrates how to highlight PDF documents with C# REST Interface. You may set different attributes such as unique ID, contents, ZIndex, horizontal alignment, vertical alignment, and subject. Note that you may set the modified and creation date properly for smooth execution of the API call.

This article has taught us to highlight PDFs online with C# .NET-based API. To add a checkbox in a PDF file, refer to the article on Add Checkbox in PDF with C# REST API.