画图函数——点，线，矩形等等

#include <windows.h>
LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
#define edge 30 //矩形边长
HBRUSH hbrush[2];//刷子数组
void paint(HDC hdc);//画图声明

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("HelloWin") ;
HWND         hwnd ;
MSG          msg ;
WNDCLASS     wndclass ;
wndclass.style         = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc   = WndProc ;
wndclass.cbClsExtra    = 0 ;
wndclass.cbWndExtra    = 0 ;
wndclass.hInstance     = hInstance ;
wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName  = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))return 0 ;
hwnd = CreateWindow (szAppName,
TEXT ("一个简单的Win32程序"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL) ;

ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;

while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{

HDC hdc;
PAINTSTRUCT ps;
switch (message)
{
case WM_PAINT:
hdc=BeginPaint(hwnd,&ps);
paint(hdc);
EndPaint(hwnd,&ps);
return 0;

case WM_DESTROY:
DeleteObject(hbrush[0]);
DeleteObject(hbrush[1]);
PostQuitMessage (0) ; //在消息队列中插入一条“退出”消息
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam);//执行默认的消息处理
}
void paint(HDC hdc)
{
int i,j;
hbrush[0]=CreateSolidBrush(RGB(255,0,0));
hbrush[1]=CreateSolidBrush(RGB(255,255,0));
for(j=0;j<3;j++) //行
for(i=0;i<3;i++)//列
{
if(j%2==0)
{

Sleep(50);
SelectObject(hdc,hbrush[0]);
Rectangle(hdc,i*edge,j*edge,(i+1)*edge,(j+1)*edge);
}
else
{
Sleep(100);
SelectObject(hdc,hbrush[1]);
Rectangle(hdc,i*edge,j*edge,(i+1)*edge,(j+1)*edge);
}

}
}