通過GetSystemMetrics 的幾個重要引數，就可以獲取顯示器的數量、當前螢幕解析度，以及總解析度：

#include "stdafx.h"
#include <Windows.h>
#include <stdio.h>

int _tmain(int argc, _TCHAR* argv[])
{
	//當前螢幕的解析度
	int nScreenWidth, nScreenHeight;
	nScreenWidth = GetSystemMetrics(SM_CXSCREEN);
	nScreenHeight = GetSystemMetrics(SM_CYSCREEN);

	printf("當前螢幕的解析度為：%d×%d", nScreenWidth, nScreenHeight);

	getchar();

	//當前螢幕數量
	int screenNum;
	screenNum = GetSystemMetrics(SM_CMONITORS);
	printf("當前螢幕數量：%d\n", screenNum);

	getchar();

	//當前螢幕總的解析度
	int aScreenWidth, aScreenHeight;
	aScreenWidth = GetSystemMetrics(SM_CXVIRTUALSCREEN);
	aScreenHeight = GetSystemMetrics(SM_CYVIRTUALSCREEN);

	printf("當前螢幕總的解析度為：%d×%d \n", aScreenWidth, aScreenHeight);

	getchar();

	return 0;
}