public string toSaveSqlString()
        {
            String sqlString = "INSERT into paylog (billno,paymode,payamount,discount,paycard,tradeid)" +
                               "VALUES('{0}','{1}',{2},{3},'{4}',{5}) ";

            return(String.Format(sqlString, BILL_NUM.ToString(), PAY_MODE, PAY_AMT.ToString(), Discount_AMT.ToString(), PAY_CARD, TRADE_ID.ToString()));
        }
        public string toSaveSqlString()
        {
            String sqlString = "INSERT into orderlog (transtype,transcode,meterialcode,volume,realamount,price,paytime,settledate,nozzleno," +
                               "startread,endread,billno,billitemid,posno,statustype,paycode,tradeid)" +
                               "VALUES('{0}','{1}','{2}', {3}, {4}, {5}, '{6}', '{7}', {8}, {9}, {10}, {11},{12},'{13}','{14}','{15}',{16}) ";

            return(String.Format(sqlString, TRANS_TYPE, TRANS_CODE, BAR_CODE, TRANS_Q.ToString(), TRANS_AMT.ToString(), TRANS_PRC.ToString(),
                                 FINISH_TIME, SETTLE_DAY, OilGun_NO.ToString(), START_READ.ToString(), END_READ.ToString(), BILL_NUM.ToString(),
                                 BILL_ITEM_ID.ToString(), POS_NO, StatusType, Pumpsrv_ref, TRADE_ID.ToString()));
        }