C# Visual Studio GPIB Commands

I use Agilent IO Library Suite.

Here is a tutorial to use it on C#: I/O programming examples in C#

Nevertheless, in my company we had stability issues with the VISA-COM implementation, so we wrote our own wrapper around the visa32.dll (also part of the IO Library suite) using P/Invoke.

(Disclosure: I work in a company that make intense use of GPIB instruments)