private void FillServiceStnVeh() { _fmsg.ServiceStnVeh = Convert.ToInt32(ddlVehicleNumber.SelectedValue); var dsServiceStn = _fmsg.GetServiceStnsVeh(); if (dsServiceStn == null) { throw new ArgumentNullException(nameof(dsServiceStn)); } switch (dsServiceStn.Tables[0].Rows.Count) { case 0: txtBunkName.Enabled = true; break; default: txtBunkName.Text = Convert.ToString(dsServiceStn.Tables[0].Rows[0][1]); break; } }