C#使用C++标准DLL实例（包含callback）

港控/mmm° 2022-04-10 21:19 235阅读 0赞

C++编写标准Win32DLL如下  
  
头文件

/*************************************************************************************************/
    /*!
        \file CppDll.h
    
        \attention
            Copyright (c) 2016  Jacky_Dai.
            All Rights Reserved.
    */
    /*************************************************************************************************/
    #ifndef CPP_DLL_H
    #define CPP_DLL_H
    
    /*** Defines/Macros/Constants/Typedefs ***********************************************************/
    #ifdef CPPDLL_EXPORTS
    #define CPPDLL_API __declspec(dllexport)
    #else
    #define CPPDLL_API __declspec(dllimport)
    #endif
    
    //Include Head files
    //
    #include <Windows.h>
    
    
    #ifdef __cplusplus
    extern "C"
    {
       
    #endif
    
    /*************************************************************************************************/
    /*!
        \brief CPP_CALLBACK 
        The callback for test.
    
        Note: Out put test data
    
        \param[out]  pbySignatureData - Reserved buffer for writing signature.
        \param[in/out]  pdwSignatureDataSize - The reserved data size / Used data size
    
        \return  Return ERR_OK if the function succeeds else nonzero error code.
    */
    /*************************************************************************************************/
    typedef DWORD (CALLBACK *CPP_CALLBACK)(PBYTE pbySignatureData, DWORD pdwSignatureDataSize);
    
    CPPDLL_API DWORD TestApp1(BYTE* pByInBuffer,
                                   DWORD dwInSize,
                                   BYTE* pByOutBuffer,
                                   DWORD* pdwOutSize);
    
    CPPDLL_API DWORD TestApp2(BYTE* pByInBuffer,
                                    DWORD dwInSize,
                                    BYTE* pByOutBuffer,
                                    DWORD* pdwOutSize,
                                    CPP_CALLBACK pCallback);
    
    CPPDLL_API DWORD TestApp3(DWORD dwVal);
    
    CPPDLL_API DWORD TestApp4(DWORD* pdwVal);
    
    #ifdef __cplusplus
    }
    #endif
    
    #endif//CPP_DLL_H

源代码

#include "CppDll.h"
    #include "stdio.h"
    #include <string.h>
    #include <time.h>
    
    DWORD TestApp1(BYTE* pByInBuffer,
                       DWORD dwInSize,
                       BYTE* pByOutBuffer,
                       DWORD* pdwOutSize)
    {
       
        if (pByOutBuffer!=NULL && pdwOutSize != NULL)
        {
       
            CHAR szTemp[1024] = {0};
            sprintf(szTemp, "[CppDll][%s] catch en error in line(%d).\r\n", __FUNCTION__, __LINE__);
    
            if (*pdwOutSize >= strlen(szTemp))
            {
       
                *pdwOutSize = (DWORD)strlen(szTemp);
                memcpy(pByOutBuffer, szTemp, strlen(szTemp));
            }
            else
            {
       
                *pdwOutSize = 0;
            }
        }
    
        return 0x0201;
    }
    
    
    DWORD TestApp2(BYTE* pByInBuffer,
                       DWORD dwInSize,
                       BYTE* pByOutBuffer,
                       DWORD* pdwOutSize,
                       CPP_CALLBACK pCallback)
    {
       
        if (pByOutBuffer!=NULL && pdwOutSize != NULL)
        {
       
            CHAR szTemp[1024] = {0};
            sprintf(szTemp, "[CppDll][%s] catch en error in line(%d).\r\n", __FUNCTION__, __LINE__);
    
            if (*pdwOutSize >= strlen(szTemp))
            {
       
                *pdwOutSize = (DWORD)strlen(szTemp);
                memcpy(pByOutBuffer, szTemp, strlen(szTemp));
    
                if (pCallback != NULL)
                {
       
                    CHAR szCallbackTemp[1024] = {0};
                    sprintf(szCallbackTemp, "[CppDll][%s] Callback output data in line(%d).\r\n", __FUNCTION__, __LINE__);
    
                    pCallback((PBYTE)(szCallbackTemp), (DWORD)strlen(szCallbackTemp));
                }
            }
            else
            {
       
                *pdwOutSize = 0;
            }
        }
    
        Sleep(500);
        return 0x0205;
    }
    
    CPPDLL_API DWORD TestApp3(DWORD dwVal)
    {
       
        if (0 == dwVal)
        {
       
            return 0;
        }
    
        return 1;
    }
    
    CPPDLL_API DWORD TestApp4(DWORD* pdwVal)
    {
       
        if (NULL != pdwVal)
        {
       
            *pdwVal = 256;
            return 0;
        }
    
        return 1;
    }

C\#写的测试代码如下

using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.Data;
    using System.Drawing;
    using System.Linq;
    using System.Text;
    using System.Windows.Forms;
    using System.Runtime.InteropServices;//DllImport
    using System.Diagnostics;//Debug
    
    namespace CSharpUsingCppCallbackDemo
    {
       
        public partial class Form1 : Form
        {
       
            public delegate uint CppCallback([MarshalAs(UnmanagedType.LPArray, SizeConst = 1024)]byte[] byOutBuffer, uint outSize);
    
    
            private const string testDll = @"C:\Users\jacky_dai\Desktop\CSharpUsingCppCallbackDemo\Debug\CppDll.dll";
    
            [DllImport(testDll)]
            public static extern uint TestApp1([In]byte[] inBuffer, [In]uint inSize, [In][Out]byte[] byOutBuffer, [In][Out]ref uint outSize);
    
            [DllImport(testDll)]
            public static extern uint TestApp2([In]byte[] inBuffer, [In]uint inSize, [In][Out]byte[] byOutBuffer, [In][Out]ref uint outSize, CppCallback pCallback);
    
            [DllImport(testDll)]
            public static extern uint TestApp3([In]uint dwVal);
    
            [DllImport(testDll)]
            public static extern uint TestApp4([In][Out]ref uint dwVal);
    
    
            public Form1()
            {
       
                InitializeComponent();
            }
    
            public uint TestCallback(/*[MarshalAs(UnmanagedType.LPArray, SizeConst=1024)]*/byte[] byOutBuffer, uint outSize)
            {
       
    
                string strMsg = System.Text.Encoding.Default.GetString(byOutBuffer);
                Debug.WriteLine(strMsg);
    
                return 0;
            }
    
            private void button1_Click(object sender, EventArgs e)
            {
       
                uint ret = 0;
                byte[] helloBuf = new byte[2048];
                byte[] tempbuffer = new byte[2048];
                uint bufSize = 2048;
    
                //ret = TestApp3(bufSize);
                //ret = TestApp4(ref bufSize);
    
                //ret = TestApp1(helloBuf, ret, tempbuffer, ref bufSize);
    
                ret = TestApp2(helloBuf, ret, tempbuffer, ref bufSize, new CppCallback(TestCallback));
    
                string strMsg = System.Text.Encoding.Default.GetString(tempbuffer);
                Debug.WriteLine(strMsg);
            }
        }
    }

[CppDll][TestApp2] Callback output data in line(50).
    [CppDll][TestApp2] catch en error in line(40).