说明：  在VB6中使用，可将透明的PNG图片叠加到背景或控件上，虽然VB6已经很少使用了，但但为制作任何UI界面的快捷方法，十分方便
(Using in VB6, transparent PNG images can be superimposed on the background or control, although VB6 has been rarely used, but it is very convenient to make any shortcut for any UI interface.)