VC6 DLL exports

//filename : Dll1.h
#ifndef _DLL1_H_ 
#define  _DLL1_H_


#ifdef DLL1_API
#else
#define DLL1_API extern "C" _declspec(dllimport)
#endif // DLL1_API

DLL1_API int _stdcall add(int a,int b);
DLL1_API int _stdcall substract(int a,int b);


#endif

　　

//filename:Dll1.cpp
#define DLL1_API extern "C" _declspec(dllexport)
#include "Dll1.h"

int _stdcall add(int a,int b)
{
	return a+b;
}

int _stdcall substract(int a,int b)
{
	return a-b;
}

　　

//MyPoint.h


// MyPoint.h: interface for the MyPoint class.
//
//////////////////////////////////////////////////////////////////////


#include <windows.h>
#include <stdio.h>

#if !defined(AFX_MYPOINT_H__0FB85FE1_A0BB_4FF3_B780_79E133776F44__INCLUDED_)
#define AFX_MYPOINT_H__0FB85FE1_A0BB_4FF3_B780_79E133776F44__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

#ifdef DLL2_API
#else
#define DLL2_API _declspec(dllimport)
#endif // DLL2_API

class DLL2_API MyPoint  
{
public:
	void output();	
	MyPoint();
	virtual ~MyPoint();
	
public:	
	int y;
	int x;
};

#endif // !defined(AFX_MYPOINT_H__0FB85FE1_A0BB_4FF3_B780_79E133776F44__INCLUDED_)

　　

// MyPoint.cpp: implementation of the MyPoint class.
//
//////////////////////////////////////////////////////////////////////

#define DLL2_API _declspec(dllexport)
#include "MyPoint.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

MyPoint::MyPoint()
{
	x=0;
	y=0;
}

MyPoint::~MyPoint()
{ 

}

void MyPoint::output()
{
	HWND hWnd = GetForegroundWindow();
	HDC hdc = GetDC(hWnd);
	char buf[40];
	memset(buf,0,40);
	sprintf(buf,"x=%d,y=%d",x,y);
	TextOut(hdc,0,0,buf,strlen(buf));
	ReleaseDC(hWnd,hdc);
}

　　

 Dll1.def

LIBRARY Dll1

EXPORTS

add
substract

　　

void CDllTestDlg::OnBtnLoadLibrary() 
{
	HMODULE hModule = LoadLibrary("Dll1.dll");
	if(!hModule)
	{
		MessageBox("未能加载DLL");
		return;
	}
	typedef  int  (_stdcall *ADDPROC) (int,int);
	ADDPROC add=(ADDPROC) GetProcAddress(hModule,"substract");
	if(!add){
		MessageBox("未找到指定函数");
		return;
	}
	int result=add(1,22);
	CString str;
	str.Format("%d",result);
	MessageBox(str);
}