//C++ ObjInf.dll
//---



#define DLL_EXPORT //省略... 
#define API  __stdcall//CallingConvention

extern "C"
{
  struct ObjInf{
    virtual Initial() = 0;
    virtual Delete() = 0;
    virtual Run(int time) = 0;
  };
  DLL_EXPORT ObjInf* API CreateObj();
};



//---
//C#


using System;
using System.Runtime.InteropServices;
namespace DllTest
{

  [StructLayout(LayoutKind.Sequential, Pack = 4, CharSet = CharSet.Ansi)]
  public struct ObjInf_vTable
  {
    [UnmanagedFunctionPointer(CallingConvention.ThisCall)]
    public delegate void funInitial(IntPtr thisPtr);

    [UnmanagedFunctionPointer(CallingConvention.ThisCall)]
    public delegate void funDelete(IntPtr thisPtr);
        
    [UnmanagedFunctionPointer(CallingConvention.ThisCall)]
    public delegate void funRun(IntPtr thisPtr , int time);

    public funInitial Initial;
    public funDelete Delete;
    public funRun Run;
  }
    
    
  [StructLayout(LayoutKind.Sequential, Pack = 4, CharSet = CharSet.Ansi)]
  public struct sObjInf
  {
    public IntPtr pTable;
  }

  class Program
  {
    [DllImport("ObjInf.dll", CallingConvention = CallingConvention.StdCall)]
    public static extern IntPtr CreateObj();


    static void Main(string[] args)
    {
      IntPtr ThisPtr = CreateObj();
      sObjInf obj = (sObjInf)Marshal.PtrToStructure(ThisPtr, typeof(sObjInf));
      ObjInf_vTable objTable = (ObjInf_vTable)Marshal.PtrToStructure(obj.pTable, typeof(ObjInf_vTable));

      objTable.Initial(ThisPtr);
    }
  }
}