windows编程经典范例，界面编程之组合框控件-classic example of windows programming，The combo box control interface programming

该程序制作了一个桌面时钟，结合MFC的各种技术，是一个学习MFC的极好的一个范例，也是学习windows编程的好资料-The program produced a desktop clock, combined with a variety of MFC technology, is an excellent example of a learning MFC, and it is good information to learn windows programming