#include "stdafx.h"

int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
// TODO: Place code here.
HDC hdc;
HWND hwnd;
hwnd=GetDesktopWindow();//得到桌面窗口句柄
hdc=GetDC(hwnd);
MoveToEx(hdc,0,0,NULL);
LineTo(hdc,180,562);
LineTo(hdc,23,232);

return 0;
}
//我想在桌面上画几个线，为什么不可以？
//希望帮我改一下，
//或说明一相原因

我再顶一 下

改在这样就可以了，

#include "stdafx.h"

int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
// TODO: Place code here.
HDC hdc;
HWND hwnd;
// hwnd=GetDesktopWindow();//得到桌面窗口句柄

hdc=GetDC(NULL);//可以
//hdc=GetDC(hwnd);
MoveToEx(hdc,0,0,NULL);
LineTo(hdc,180,562);
LineTo(hdc,23,232);
ReleaseDC(NULL, hdc);

return 0;
}