c# 导入c++ dll

1.类的函数的内联实现
#include "stdafx.h"
#include "testdll.h"
#include <iostream>
#include "testdll.h"
using namespace std;
#ifndef TestDll_H_
#define TestDll_H_
#pragma once
#define DLL_EXPORTS
#ifdef DLL_EXPORTS
//#define DLL_API extern "C"  __declspec(dllexport)
#define DLL_CLASS __declspec(dllexport)
#else
/*#define DLL_API extern "C"  __declspec(dllimport) */
#define DLL_CLASS __declspec(dllimport)
#endif  

#include <iostream>
//DLL_CLASS是关键字不可缺省

	class DLL_CLASS MyOGRE1
	{
	public:
		void MyOGREHello()
		{
			std::cout << "Hello MyOGRE_Hello()" <<"NIMEI"<< std::endl;
		}

	};

#endif  

2.函数的声明与实现分开
.h文件
using namespace std;
#ifndef TestDll_H_
#define TestDll_H_
#pragma once
#define DLL_EXPORTS
#ifdef DLL_EXPORTS
//#define DLL_API extern "C" __declspec(dllexport)
#define DLL_CLASS __declspec(dllexport)
#else
/*#define DLL_API extern "C" __declspec(dllimport) */
#define DLL_CLASS __declspec(dllimport)
#endif
class DLL_CLASS MyOGRE1
{
public:
void MyOGREHello();

};

#endif 

cpp文件
#include "stdafx.h"
#include "testdll.h"
#include <iostream>
#include "testdll.h"
using namespace std;
void MyOGRE1::MyOGREHello()
{
cout << "66666" << endl;
}

c#代码
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApplication17
{
    [StructLayout(LayoutKind.Sequential)]
    public class MyOGRE
    {
        //该方式是直接调用C++ DLL内的类的成员函数。  QAEXXZ
        [DllImport("MyDLL.dll", EntryPoint = "?MyOGREHello@MyOGRE1@@QAEXXZ")]
        public static extern void MyOGREHello();
    }
    class Program
    {

        #region 1
        static void Main(string[] args)
        {

            MyOGRE.MyOGREHello();

            Console.ReadKey();
        }

        #endregion
    }
}