转：Delphi 回调函数及例子

http://anony3721.blog.163.com/blog/static/5119742010866050589/

{
  http://anony3721.blog.163.com/blog/static/5119742010866050589/ 例子出处
}
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs,StdCtrls;

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
    {定义一个用于回调的过程}
    procedure test(str:string);
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation
{引用unit2}
uses unit2;
{$R *.dfm}
{回调过程的实现部分}
procedure TForm1.test(str: string);
begin
  {将str值副给Edit1}
  Edit1.Text:=str;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
    {调用Unit2的接口方法}
    CallUnit2(test);
end;

end.

unit Unit1