How about this site:
http://www.programmersheaven.com/mb/csharp/346567/346567/integrating-a-dll-into-c/?S=B20000Kurt
>I am working on converting a foxpro program to c#. In my foxpro program I use some functions in a dll with a setup like this:
>
>DECLARE INTEGER Dial IN autodial.dll
> INTEGER nPortNum, STRING cdial
>
>Then I call it like this:
>
>Dial(nHandle,"8005551212")
>
>Can anyone direct me to an article that shows how to use this same dll in c#? And how to call it, etc.? Thanks!!!!
>
>Bob