Filling Adobe LiveCycle Forms ES2 using C#

I have just got a task to open PDF form and fill it using the application writt开发者_运维问答en in C#. Is there an API to work with PDF forms from Microsoft .NET?

What kind of form? If this is a so-called Acroform (i.e. forms created with Adobe Acrobat), you can simply use iTextSharp (free and open source) to fill in the form. If this is a "XFA-Forms" (i.e. forms created with Adobe LiveCycle Designer), you will need Adobe LiveCycle Forms (you can call its API via SOAP,it is a close and commercially available product) or, with some limitations, iTextSharp.

Link for iTextSharp: http://sourceforge.net/projects/itextsharp/