#cpp
private void doWork_2(object data, int index) {
  string str = TextBox3.Text;
  switch (index) {
  case 0:
    Label4.Text = ; // ????????----- бардак ---------???????????

    break;
  case 1:
    Label6.Text = Convert.ToString(data);

    break;
  default:
    Label6.Text = Convert.ToString(index);

    break;
  }
}