GDI图形编程，能绘制矩形、椭圆、圆、填充矩形等，并实现一个树形列表列出图形对象，选中能闪烁，显示图形对象属性-GDI graphics programming, can draw rectangular, oval, round, filled rectangle, and set out to achieve a graphic object tree list, select to flash, display graphics object properties