Работа с Sender

unit TestInputForm;

interface

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

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Label1: TLabel;
    DdhInputButton1: TDdhInputButton;
    DdhInputButton2: TDdhInputButton;
    DdhInputButton3: TDdhInputButton;
    procedure DdhInputButtonClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.DdhInputButtonClick(Sender: TObject);
begin
  ShowMessage ('You''ve clicked the ' +
    (Sender as TButton).Name + ','#13 +
    'having the caption ' +
    (Sender as TButton).Caption);
end;

end.