How to use C functions from dll in .net(C#)?

If there's a dll written on C, then how is it possible to use it in .net(C#)?

Is it strictly necessary to write a header file for it in order to data types be compatible b开发者_Python百科etween two languages?

You already know about P/invoke from your previous question. Regarding the header file, it's not used for managed interop. Instead the P/invoke declarations specify the function parameters, calling conventions etc.

Yes, it's possible. It's called unmanaged DLL. There are quite a few tutorials in this regards. One of them i had from before when i was working in this similar aspect is: [1] http://www.codeproject.com/KB/mcpp/usingcppdll.aspx