Calling a C# function from a C++ DLL

Question

I have a DLL written in C++, and I want to pass a C# function to a function in the C++ DLL and call the C# function from C++. How would I do this? Thanks in advance, and please

Answer 1

There are generally two ways to accomplish this: COM Interop and Reverse PInvoke. If you are passing around a lot of objects with behaviors then COM interop is likely you're best bet. Here though it sounds like you're just trying to pass a single function around. If so then Reverse PInvoke is what you want.

Here is a nice tutorial on the subject

• http://tigerang.blogspot.com/2008/09/reverse-pinvoke.html
• http://blogs.msdn.com/b/thottams/archive/2007/06/02/pinvoke-reverse-pinvoke-and-stdcall-cdecl.aspx

The basic process though is fairly similar to normal PInvoke.

• Define a native entry point which takes at least one function pointer
• Define the native pointer as a delegate in managed code
• Pass the delegate down through the entry point

It can now be invoked as a normal function pointer in native code