Managed C++/CLI

#using <mscorlib.dll>
#import "C:\\Programing\\Projects\\Visual Basic\\native calls\\vchash\\ManagedDLL\\ManagedDLL\\bin\\Debug\\ManagedDLL.tlb" raw_interfaces_only

using namespace ManagedDLL;
void CCallingExeDlg::OnBnClickedOk()
{
    HRESULT hr = CoInitialize(NULL);
    ICalculatorPtr pICalc(__uuidof(ManagedClass));
}

using System;
using System.Runtime.InteropServices;

namespace ManagedDLL
{
    [ComVisible(true)]
    [Guid("1A9ECDD2-24FC-4f9b-97BF-BF170B16CB38")]
    // Interface declaration.
    public interface ICalculator
    {
        int Add(int Number1, int Number2);
    };
    [ComVisible(true)]
    [Guid("9CEFF09D-7140-451e-A85E-2341A7C978FA")]
    // Interface implementation.
    public class ManagedClass : ICalculator
    {
        public int Add(int Number1, int Number2)
        {
            return Number1 + Number2;
        }
    }
}