unit Unit1;  interface  uses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls;  type   TShowInfo = procedure(info:string) of object;  //聲明一個procedure類型，參數和ShowInfo一致   TForm1 = class(TForm)   Button1: TButton;   procedure Button1Click(Sender: TObject);  private   { Private declarations }  public   { Public declarations }   published   procedure ShowInfo(info:string);  end;  var  Form1: TForm1;  implementation  {$R *.dfm}  { TForm1 }  procedure TForm1.ShowInfo(info: string); begin  ShowMessage(info); end;  procedure TForm1.Button1Click(Sender: TObject); var  s:TShowInfo; begin  @s := MethodAddress('ShowInfo');    //取得ShowInfo的地址  if @s <> nil then           //如果不為空  begin   s('中華人民共和國');         //執行  end; end;  end.