用WindowFromPoint()函数来获得鼠标所在位置的窗口的句柄--发生一个关闭窗口的消息---关闭鼠标所在的窗口

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

int _tmain(int argc, _TCHAR* argv[])
{
 POINT curpos;
 while (TRUE)
 {
  GetCursorPos(&curpos);
  HWND wnd = WindowFromPoint(curpos);
  SendMessage(wnd, WM_CLOSE, 0, 0);
  Sleep(1000);
 }
 
 return 0;
}

HWND WindowFromPoint(  POINT Point);

Return Value
Returns a handle to the window that contains the x-y coordinates to indicate success. Returns NULL to indicate that no window exists at the specified x-y coordinates.
//返回一个句柄,表示成功,返回NULL表示失败. 返回的这个窗口句柄是: 鼠标curpos结构体所在窗口里面的句柄被返回.
//句柄是一个整数.
Remarks
The WindowFromPoint function does not retrieve a handle to a hidden or disabled window, even if the x-y coordinate is within the window. To determine if child windows of a parent window contain an x-y coordinate, use the ChildWindowFromPoint function.
//这个函数不检索窗口被disabled的,不检索窗口被隐藏的,不返回这两个类型的句柄.