Hi Nick,

Currently I understand that you would like to create a .NET class and
expose it to COM and call it from C++.
If I misunderstand, please let me know.

Here I write some code snippet for your reference.
1. .NET Server
using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;

namespace dotNETServer
{
   [InterfaceType(ComInterfaceType.InterfaceIsDual),ComVisible(true)]
   public interface ITest
   {
       string HelloWorld();
   }
   [ClassInterface(ClassInterfaceType.None),ComVisible(true)]
   public class TestClass :ITest
   {
       #region ITest Members

       public string HelloWorld()
       {
           return "Hello World!";
       }

       #endregion
   }
}

2. C++ client
// TestConsole.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#import "..\\dotNETServer\\bin\\Debug\\dotNETServer.tlb"
#include <comdef.h>
int _tmain(int argc, _TCHAR* argv[])
{
    CoInitialize(NULL);
    dotNETServer::ITestPtr pdotNETServer;
    HRESULT hr    =
pdotNETServer.CreateInstance(__uuidof(dotNETServer::TestClass));
    try
    {
        if FAILED(hr)
        {
            _com_issue_error(hr);
        }
        else
        {
            _bstr_t resultStr = pdotNETServer->HelloWorld();
            printf("%S\n",(LPCWSTR)resultStr);
        }
    }
    catch(_com_error &e)
    {
        printf("%S\n", e.ErrorMessage());
    }
    CoUninitialize();
    return 0;
}

You may have a try and let me know the result.

BTW: here is a link for your reference.
.NET - COM Interoperability
http://www.codeproject.com/dotnet/COM_DOTNET_INTEROP.asp?print=true

Best regards,

Perter Huang
Microsoft Online Partner Support

Hi,

Just want to say Hi, and I was wondering how everything is going.
If anything is unclear, please let me know.
It is my pleasure to be of assistance.

Best regards,

Peter Huang

Microsoft Online Community Support
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