说明：  CBtnEx继承自CButton，是在VC++6.0环境下编写的按钮扩展类。按钮的外形可以为自定义的多边形、椭圆， 或由位图中抠出的图形决定。按钮的侧面棱边可为平面或为圆弧状的平滑过渡。可以为按钮设置三种状态下（未激活、鼠标在按钮上、鼠标按下）按钮表面、按钮棱边以及按钮上文字的颜色。同时可为按钮设置焦点框、贴图、ToolTip等细节内容。
(CBtnEx inherited from CButton, is in VC++6.0 environment prepared by button extension classes. Button shape for a custom polygon, ellipse, or plucked out of a bitmap graphic decision. Button on the side of the plane or edge for a smooth transition for the arc-shaped. You can set three conditions for the button (not activated, the mouse button, mouse click) the button face, button and the button on the edge color of the text. At the same time frame for the button to set focus, mapping, ToolTip and other details.)