What are my options for C++ DLL to call a C# DLL?

Question

I have a C++ DLL that needs to call a function (pass a value, return a value) in a C# class library.

Is my only option to give the C# DLL a COM interface and call it from C++ with IDispatch?

Is this the best method?

Answer 1

One approach that would work would be to call it though COM. You can use the Regasm tool to create the COM wrapper.

Answer 2

It's not the only option.

You could also compile your C++ DLL as a managed DLL.

You could host your C# DLL as a service and remote into it.

Answer 3

Couple of options available for you here

1. Use a mixed mode C++/CLI assembly as a bridge between the C++ and C# DLL
2. Use the a COM bridge by exposing several of the key C# types as COM objects. This can then be accessed via the C++ code by normal COM semantics