Конструкция Delphi

  if (Sender is TButton) then
    with (Sender as TButton) do
      begin
        Caption:='Test';
        Tag:=100;
      end;

procedure TMainForm.EditKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var i : integer;
    Control : TWinControl;
    Button : TBitBtn;
 
begin
Control := TCustomControl(Sender).Parent;
 
 if Key = VK_RETURN then
  for i := 0 to Control.ControlCount - 1 do
    if Control.Controls[i].ClassType = TBitBtn then
    begin
     Button := (Control.Controls[i] as TBitBtn);
      if (Button.Caption = 'Добавить')
        or (Button.Caption = 'Показать')
      then Button.OnClick(Button);
end;

procedure TForm1.MyButtonClick(Sender: TObject);
begin
  with (Sender as TBitBtn) do
    begin
      case Tag of
        1: ShowMessage('Нажали кнопку "Создать"');
        2: ShowMessage('Нажали кнопку "Показать"');
      end;
    end;
end;
 
 
procedure TForm1.FormCreate(Sender: TObject);
begin
  BitBtn1.Tag:=1;
  BitBtn2.Tag:=2;
  BitBtn1.OnClick:=MyButtonClick;
  BitBtn2.OnClick:=MyButtonClick;
end;

if ((sender as TWinControl).parent as TAdvDBPanel.Tag)=1 then
begin
  DoShow();
end
else
begin
  DoAppend();
end;

procedure TMainForm.FormKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var i : integer;
    ParentControl : TWinControl;
    Button : TBitBtn;
begin
 ParentControl := Screen.ActiveControl.Parent;
 {
 if (Sender is TAdvComboBox) then
 if (Sender as TAdvComboBox).Style <> csOwnerDrawFixed
 then LookupComboBoxChange(Sender);   }
 
 if (Key = VK_RETURN) and (ParentControl is TAdvDBFormPanel) then
  for i := 0 to ParentControl.ControlCount - 1 do
    if ParentControl.Controls[i].ClassType = TBitBtn then
    begin
     Button := (ParentControl.Controls[i] as TBitBtn);
      if (Button.Caption = 'Показать')
        or (Button.Caption = 'Добавить')
      then
      begin
        Button.OnClick(Button);
        Break;
      end;
    end;
end;