《windows程序设计》学习_3.2：左键的使用

 #include<windows.h>
 #include "resource.h"

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

 int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstace, PSTR szCmdLine, int iCmdShow)
 {
     static TCHAR szAppName[] = TEXT ("Stick1");
     HWND        hwnd;
     MSG         msg;
     WNDCLASS    wndclass;

     wndclass.style                  = CS_HREDRAW | CS_VREDRAW ;
     wndclass.lpfnWndProc            = WndProc;
     wndclass.cbClsExtra             = ;
     wndclass.cbWndExtra             = ;
     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 ("The Program requires Windows NT!"), szAppName, MB_ICONERROR);
         return ;
     }

     hwnd = CreateWindow (szAppName,
                         TEXT ("Stick 1"),
                         WS_OVERLAPPEDWINDOW,
                         CW_USEDEFAULT,
                         CW_USEDEFAULT,
                         CW_USEDEFAULT,
                         CW_USEDEFAULT,
                         NULL,
                         NULL,
                         hInstance,
                         NULL);

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

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

 LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
 {
     static HBITMAP hBitmap;
     static int     cxClient, cyClient, cxSource, cySource;
     BITMAP         bitmap;
     HDC            hdc,hdcMem;
     HINSTANCE      hInstance;
     int            x,y;
 //    PAINTSTRUCT    ps;

     switch(message)
     {
     case WM_CREATE:
         hInstance = ((LPCREATESTRUCT) lParam) ->hInstance;

         hBitmap = LoadBitmap(hInstance,MAKEINTRESOURCE(IDM_BITMAP)/*TEXT("bitmap1")*/);
         GetObject(hBitmap,sizeof(BITMAP),&bitmap);

         cxSource = bitmap.bmWidth;
         cySource = bitmap.bmHeight;

         return ;

     case WM_LBUTTONDOWN:
         hdc = GetDC(hwnd);

         hdcMem = CreateCompatibleDC(hdc);
         SelectObject(hdcMem, hBitmap);

         x = LOWORD(lParam);
         y = HIWORD(lParam);

         BitBlt(hdc, x, y, cxSource, cySource, hdcMem, , , SRCCOPY);

         DeleteDC(hdcMem);
         ReleaseDC(hwnd, hdc);
         return ;
     case WM_DESTROY:
         DeleteObject(hBitmap);
         PostQuitMessage();
         return ;
     }
     return DefWindowProc(hwnd, message, wParam, lParam);
 }