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c#.netc++ipc

Interprocess communication between C# and C++


I'm writing a bot for a game, which has a C++ API interface (ie. methods in a Cpp dll get called by the game when events occur, the dll can call back methods in the game to trigger actions).

I don't really want to write my bot in C++, I'm a fairly experienced C# programmer but I have no C++ experience at all. So, the obvious solution is to use ipc to send event to a C# program, and send actions back to the C++ one, that way all I need to write in C++ is a basic framework for calling methods and sending events.

What would be the best way to do this? Sample code would be greatly appreciated as I no have particular desire to learn C++ at this point!


Solution

  • One solution is to create a managed C++ class library with regular __declspec(dllexport) functions which call managed methods in a referenced C# class library.

    Example - C++ code file in managed C++ project:

    #include "stdafx.h"
    
    __declspec(dllexport) int Foo(int bar) 
    {
        csharpmodule::CSharpModule mod;
        return mod.Foo(bar);
    }
    

    C# Module (separate project in solution):

    namespace csharpmodule
    {
        public class CSharpModule
        {
            public int Foo(int bar)
            {
                MessageBox.Show("Foo(" + bar + ")");
                return bar;
            }
        }
    }
    

    Note that I am demonstrating that this is an actual .NET call by using a System.Windows.Forms.MessageBox.Show call.

    Sample basic (non-CLR) Win32 console application:

    __declspec(dllimport) int Foo(int bar);
    
    int _tmain(int argc, _TCHAR* argv[])
    {
        std::cout << Foo(5) << std::endl;
        return 0;
    }
    

    Remember to link the Win32 console application with the .lib file resulting from the build of the managed C++ project.