offsetrgn.c

C#一个实例源代码

/*--------------------------------------------------
  OffstRgn.c
  --------------------------------------------------*/
#include <windows.h>

LRESULT CALLBACK MainWndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow)
{
     static TCHAR szAppName[] = TEXT ("OffstRgn") ;
     HWND         hwnd ;
     MSG          msg ;
     WNDCLASS     wndclass ;
     
     wndclass.style         = CS_HREDRAW | CS_VREDRAW ;
     wndclass.lpfnWndProc   = MainWndProc ;
     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))
     {
          MessageBox (NULL, TEXT ("Program requires Windows NT!"), 
                      szAppName, MB_ICONERROR) ;
          return 0 ;
     }
     
     hwnd = CreateWindow (szAppName, TEXT ("OffsetRgn"),
                          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 MainWndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
     HDC              hdc ;
     PAINTSTRUCT      ps ;
     HRGN             hrgnA, hrgnB, hrgnC;
     int              nOffsetResult,nCombineResult;
     HBRUSH           hbrA, hbrB, hbrC;

     switch (message)

     {
     case WM_PAINT :
          hdc = BeginPaint (hwnd, &ps) ;

        hrgnA=CreateEllipticRgn(200, 100, 350, 250);
		hrgnB=CreateEllipticRgn(200, 100, 350, 250);
		nOffsetResult = OffsetRgn(hrgnB, -75, 75 );
	
		hrgnC=CreateRectRgn( 0, 0, 1, 1);
		nCombineResult =CombineRgn(hrgnC,hrgnA,hrgnB, RGN_AND );

		hbrC=CreateHatchBrush( HS_FDIAGONAL, RGB(0, 0, 255)); // Blue
		FillRgn( hdc,hrgnC, hbrC );
		hbrA=CreateSolidBrush( RGB(255, 0, 0));  // rgnA Red
		FrameRgn( hdc,hrgnA, hbrA, 2, 2 );
		hbrB=CreateSolidBrush( RGB(0, 255, 0) );  // rgnB Green
		FrameRgn( hdc,hrgnB, hbrB, 2, 2 );   

		DeleteObject(hrgnA);
		DeleteObject(hrgnB);
		DeleteObject(hrgnC);
		DeleteObject(hbrA);
		DeleteObject(hbrB);
		DeleteObject(hbrC);
		  
		  EndPaint (hwnd, &ps) ;
          return 0 ;

     case WM_DESTROY :
		  PostQuitMessage (0) ;
          return 0 ;
     }
     return DefWindowProc (hwnd, message, wParam, lParam) ;
}