大牛帮看下这个程序 为什么没反应。

unit CRefForm;

interface

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

type
  // Class reference type (redeclaration)
  TControlClass = class of TControl;

  TCRefForm1 = class(TForm)
    Panel1: TPanel;
    RbtnRadio: TRadioButton;
    RbtnButton: TRadioButton;
    RbtnEdit: TRadioButton;
    procedure RbtnEditClick(Sender: TObject);
    procedure RbtnButtonClick(Sender: TObject);
    procedure RbtnRadioClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure FormMouseDown(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
  private
    { Private declarations }
    ClassRef: TControlClass;
    Counter: Integer;
  public
    { Public declarations }
  end;

var
  CRefForm1: TCRefForm1;

implementation

{$R *.dfm}

procedure TCRefForm1.RbtnButtonClick(Sender: TObject);
begin
  ClassRef := TButton;
end;

procedure TCRefForm1.RbtnEditClick(Sender: TObject);
begin
  ClassRef := TEdit;
end;

procedure TCRefForm1.RbtnRadioClick(Sender: TObject);
begin
  ClassRef := TRadioButton;
end;

procedure TCRefForm1.FormCreate(Sender: TObject);
begin
  ClassRef := TRadioButton;
end;

procedure TCRefForm1.FormMouseDown(
  Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
Var
  NewCtrl: TControl;
  CtrlName: string;
begin
  // Create the Control
  NewCtrl := ClassRef.Create(Self);
  // hide it temporarily, to avoid flickering
  NewCtrl.Visible := False;
  // set parent and position
  NewCtrl.Parent := Self;
  NewCtrl.Left := X;
  NewCtrl.Top := Y;
  // compute the unique name (and caption)
  Inc(Counter);
  CtrlName := ClassRef.ClassName + IntToStr(Counter);
  Delete (CtrlName, 1, 1);
  NewCtrl.Name := CtrlName;
  NewCtrl.Visible := True;
end;

end.

program ClassReference;

uses
  Forms,
  CRefForm in 'CRefForm.pas' {CRefForm1};

{$R *.res}

begin
  Application.Initialize;
  Application.CreateForm(TCRefForm1, CRefForm1);
  Application.Run;
end.