Side-By-Side COM Interop with C# and VBA

Question

I\'m not talking about calling a VBA COM from C#... the other way around!

What I would like to do is call a C# library using VBA in MS Access without registering the

Answer 1

The problem is that to use SxS, you need to own the exe to set up the config to load the SxS assembly. You don't "own" Access, and while you could drop the right config in to cause it to load your .NET COM stuff sans registration, it wouldn't be a "good citizen" move.

If you get tricky with shimming, you can set up an unmanaged DLL (or a hacked C# class library with a dllexport, see this, for example) with an export that will load the .NET framework, create an instance of a COMVisible DispInterface managed type and return it (the method should return IDispatch). Then write a VBA declare to your DLL export function (declared as returning Object). If this doesn't make sense, you probably oughtn't try it... :) I've done this before in a similar situation, and it does work, but I don't have a sample to point you at.