(1)首先创建主窗口时,在其属性中加上:WS_HSCROLL:hwnd = CreateWindow (szAppName, TEXT ("Button Look"),   WS_OVERLAPPEDWINDOW | WS_HSCROLL | WS_VSCROLL,//WS_HSCROLL表示有滚动条                          CW_USEDEFAULT, CW_USEDE