I need to work with the Windows API. I've read the help file in VB, MSDN, and other websites, and I can't seem to find any information for things like how to get started writing the code from scratch. There is a walkthrough on MSDN for an example, but it seems that it assumes you know a lot already. It doesn't say how it got some of the information that it tells me to put into my example program, for example the parameters, etc.

This is one example:

VB Code:
  1. DllImport(CharSet:=CharSet.Unicode, ExactSpelling:=True)

It displays this as something I need to put this in my code, but it doesn't say why to use CharSet and any of those values, and it doesn't say how I'm supposed tell when I need to use values like this.

Also, it doesn't say why to use ByVal, etc.

Obviously, I have a lot to learn. Does anyone know of any books for beginners for Windows API .NET, or any way that I can learn this by myself?