I am trying to implement an "out of proc" COM server written in C#. How do I do this?
I need the C# code to be "out of proc" from my main C++ application, because I cannot load the .NET runtime into my main process space
WHY?:
My C++ code is in a DLL that is loaded into many different customer EXE's, some of which use different versions of the .NET runtime. Since there can only be one runtime loaded into a single process, my best bet seems to be to put my C# code into another process.
You can create COM+ components using System.EnterpriseServices.ServicedComponent. Consequently, you'll be able to create out-of-proc and in-proc (client) component activation as well as all COM+ benefits of pooling, remoting, run as a windows service etc.
Here we can read that it is possible, but the exe will be loaded as an library and not started in it's own process like an exe. I don't know if that is a problem for you? It also contains some possible solutions if you do want to make it act like a real out of process com server. But maybe using another way of inter process communication is better. Like .Net Remoting.
I cannot recommend this as the way, but you could create a COM-callable wrapper for your C# library, then create a VB6 ActiveX exe project that delegates calls to your C# library.
Why can't you load the .net runtime into you process space? It is possible to host the .net runtime and call into .net using COM.
来源：https://stackoverflow.com/questions/30653/what-do-i-need-to-do-to-implement-an-out-of-proc-com-server-in-c