先讲一下LoadBitmap的用法，代码如下：

PAINTSTRUCT ps;    HDC hdc = BeginPaint(hwnd,&ps);    HDC hMemDC = CreateCompatibleDC(hdc);    HBITMAP hBitmap = LoadBitmap(g_hIntance,MAKEINTRESOURCE(IDB_BITMAP1));    HBITMAP hOldBitmap = (HBITMAP)SelectObject(hMemDC,hBitmap);        //把HBITMAP转换成BITMAP，从而获取位图的宽高。    BITMAP bmp;    GetObject(hBitmap, sizeof(BITMAP), &bmp);    BitBlt(hdc,0,0,bmp.bmWidth,bmp.bmHeight,hMemDC,0,0,SRCCOPY);    SelectObject(hMemDC,hOldBitmap);    DeleteObject(hBitmap);    DeleteDC(hMemDC);    EndPaint(hwnd,&ps);

BitBlt的作用是把hMemDC上的内容拷贝到hdc上，不进行缩放，但是可以位移。

如果想要缩放，可以使用StretchBlt,以下这个例子比较有趣，是把整个屏幕绘制到窗口中。

PAINTSTRUCT ps;    HDC hdcClient = BeginPaint(hwnd, &ps);      HDC hdcScreen = CreateDC(TEXT("DISPLAY"), NULL, NULL, NULL);      RECT rtClient;    int scrWidth = GetSystemMetrics(SM_CXSCREEN);    int scrHeight = GetSystemMetrics(SM_CYSCREEN);    GetClientRect(hwnd,&rtClient);    StretchBlt(hdcClient,0,0,rtClient.right,rtClient.bottom,        hdcScreen,0,0,scrWidth,scrHeight,SRCCOPY);    DeleteDC(hdcScreen);      EndPaint(hwnd, &ps);