iText ® is a library that allows you to create and manipulate PDF documents. It enables developers looking to enhance web- and other applications with dynamic PDF document generation and/or manipulation.
Developers can use iText to:
Serve PDF to a browser
Generate dynamic documents from XML files or databases
Use PDF’s many interactive features
Add bookmarks, page numbers, watermarks, etc.
Split, concatenate, and manipulate PDF pages
Automate filling out of PDF forms
Add digital signatures to a PDF file
iText is available in Java as well as in C#.