public bool insertNewBill(DateTime daySales, double total, double guestMoney, double excessCash, int totalNum, int POS, string accountCode) { try { using (var db = new CMART2Entities1()) { ObjectParameter idoutput = new ObjectParameter("ID", typeof(String)); db.SP_BILL_ID_AUTO_Test(idoutput); var id_auto = idoutput.Value.ToString(); var bill = new Bill { BallotNum = id_auto, Date = daySales, Total = total, GuestMoney = guestMoney, ExcessCash = excessCash, TotalNum = totalNum, POS = POS, AccountCode = accountCode }; db.Bills.Add(bill); db.SaveChanges(); id = Convert.ToString(id_auto); return(true); } } catch (Exception) { return(false); } }