delphi中赋值对象

procedure TDateForm.FormCreate(Sender: TObject);
begin
  TheDay := TDate.Create (2003, 12, 25);
  LabelDate.Caption := TheDay.GetText;
end;

procedure TDateForm.BtnTodayClick(Sender: TObject);
var
  NewDay: TDate;
begin
  NewDay := TDate.Create;
  TheDay.Assign(NewDay);
  LabelDate.Caption := TheDay.GetText;
  NewDay.Free;
end;

如果是用:　　

TheDay:=NewDay;

这样会为每一个新对象分配内存，却不能释放TheDay变量以前指向的对象的内存