学步园

 关键字：MethodAddress：取得方法的地址，这个方法需要是published的。

unit Unit1;</p> <p>interface</p> <p>uses<br /> Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,<br /> Dialogs, StdCtrls;</p> <p>type</p> <p> TShowInfo = procedure(info:string) of object; //声明一个procedure类型，参数和ShowInfo一致</p> <p> TForm1 = class(TForm)<br /> Button1: TButton;<br /> procedure Button1Click(Sender: TObject);<br /> private<br /> { Private declarations }<br /> public<br /> { Public declarations }</p> <p> published<br /> procedure ShowInfo(info:string);<br /> end;</p> <p>var<br /> Form1: TForm1;</p> <p>implementation</p> <p>{$R *.dfm}</p> <p>{ TForm1 }</p> <p>procedure TForm1.ShowInfo(info: string);<br /> begin<br /> ShowMessage(info);<br /> end;</p> <p>procedure TForm1.Button1Click(Sender: TObject);<br /> var<br /> s:TShowInfo;<br /> begin<br /> @s := MethodAddress('ShowInfo'); //取得ShowInfo的地址<br /> if @s <> nil then //如果不为空<br /> begin<br /> s('中华人民共和国'); //执行<br /> end;<br /> end;</p> <p>end.<br />