public void GetInvoiceNo(string OrderID) { CustomProfile profile = CustomProfile.GetProfile(); iPartRequestClient objService = new iPartRequestClient(); string InvNo = objService.GetInvoiceNoofOrder(long.Parse(OrderID), profile.DBConnection._constr); if (InvNo == "0") { txtInvoiceNo.Text = ""; } else { txtInvoiceNo.Text = InvNo; } }