[Alan85]

Код:

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure OnClik(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation
{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
 var b:tbutton;
begin
 b:=TButton.Create(form1);
 b.Parent:=form1;
 b.OnClick:=OnClik;
 b.Visible:=true;
end;

procedure TForm1.OnClik(Sender: TObject);
begin
 ShowMessage('hello');
end;

end.

небольшой пример