type
 TForm1 = class(TForm)
 private
  procedure CMDialogKey(var msg: TCMDialogKey);
  message CM_DIALOGKEY;
 end;
var
 Form1: TForm1;
implementation
{$R *.DFM}
procedure TForm1.CMDialogKey(var msg: TCMDialogKey);
begin
 if msg.Charcode <> VK_TAB then
  inherited;
end;
procedure TForm1.FormKeyDown(Sender: TObject; var Key:
 Word; Shift: TShiftState);
begin
 if Key = VK_TAB then
  Form1.Caption := 'Tab Key Down!';
end;