画图函数——点，线，矩形等等

矩形应用，画一个3行3列的矩形组合

#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);    
                }

        }
}