win32 api calls

To supplement the article which Bechir found, here are a couple more articles which are particularly good for developers who have no previous experience of calling Win32 functions from C#:

http://msdn.microsoft.com/en-gb/magazine/cc164123.aspx

http://msdn.microsoft.com/en-us/magazine/cc163910.aspx

Also the following is a great site for looking up the C# or VB.Net signatures of Win32 functions and (if you're lucky) finding examples of usage:

http://www.pinvoke.net/