奇妙的tag属性delphi想的太周到了

官方的说法 这样的我以后 就不用定义多余的变量来判断 是点击的修改按钮还是增加按钮了

Stores an integer value as part of a component.

Tag has no predefined meaning. The Tag property is provided for the convenience of developers. It can be used for storing an additional integer value or it can be typecast to any 32-bit value such as a component reference or a pointer.