DLL基础

Visual C++在创建DLL导出函数时，可能会对原始的函数名做修改。例如：

int WINAPI Add(int nLeft, int nRight)

导出后的函数名称是_Add@8。

下面两种方法可使编译器不对导出函数名称做修改：

1. 使用def文件
2. 在代码中添加：#pragma comment(linker, “/export:Add=_Add@8”)

MyLib.h

#ifdef MYLIB_EXPORTS#define MYLIBAPI extern "C" __declspec(dllexport)#else#define MYLIBAPI extern "C" __declspec(dllimport)#endifMYLIBAPI int g_nResult;//MYLIBAPI int Add(int nLeft, int nRight);
MYLIBAPI int WINAPI Add(int nLeft, int nRight);

MyLibFile1.cpp

#include <windows.h>
#include "MyLib.h"#pragma comment(linker, "/export:Add=_Add@8")int g_nResult;//int Add(int nLeft, int nRight)
int WINAPI Add(int nLeft, int nRight)
{
    g_nResult = nLeft + nRight;
    return g_nResult;
}

MyLib.def

EXPORTS
  Add

MyExeFile1.cpp

#include <windows.h>
#include <strsafe.h>
#include <stdlib.h>#include "..\MyLib.h"int WINAPI WinMain(HINSTANCE , HINSTANCE , LPTSTR , int)
{
    int nLeft = , nRight = ;    TCHAR sz[];
    StringCchPrintf(sz, sizeof(sz)/sizeof(sz[]), TEXT("%d + %d = %d"),
        nLeft, nRight, Add(nLeft, nRight));
    MessageBox(NULL, sz, TEXT("Calculation"), MB_OK);    StringCchPrintf(sz, sizeof(sz)/sizeof(sz[]),
        TEXT("The result from the last Add is: %d"), g_nResult);
    MessageBox(NULL, sz, TEXT("Last Result"), MB_OK);    return ;
}