delphi 中的函数指针 回调函数

以下代码仅仅是测试代码：delphi XE7 UP1

interfaceuses  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,  System.Classes, Vcl.Graphics,  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;type  TForm1 = class(TForm)    btn1: TButton;    btn2: TButton;    edt1: TEdit;    procedure btn1Click(Sender: TObject);    procedure FormCreate(Sender: TObject);    procedure FormShow(Sender: TObject);    procedure FormDestroy(Sender: TObject);  private    { Private declarations }  public    { Public declarations }  end;  TMethod = procedure(v:string);var  Form1: TForm1;  FList: TList;implementation{$R *.dfm}procedure p1(v:string);begin  ShowMessage('p1'+v);end;procedure p2(v:string);begin  ShowMessage('p2'+v);end;procedure callt(my:TMethod;v:string);begin  my(v);end;procedure TForm1.btn1Click(Sender: TObject);var  v_s:string;begin  v_s:= edt1.Text;  callt(FList.Items[StrToInt(v_s)],v_s);end;procedure TForm1.FormCreate(Sender: TObject);begin   FList := TList.Create;end;procedure TForm1.FormShow(Sender: TObject);begin  FList.Add(@p1);  FList.Add(@p2);  edt1.Clear;end;procedure TForm1.FormDestroy(Sender: TObject);begin  FreeAndNil(FList);end;end.