订单号生成办法

1、Redis Incr

public class RedisConnection
    {
        private static readonly ConfigurationOptions ConfigurationOptions = ConfigurationOptions.Parse("127.0.0.1" + ":" + "6379");
        private static ConnectionMultiplexer _redisConn;
        private static readonly object Locker = new object();
        private RedisConnection() { }  

        /// <summary>
        /// 单例获取Redis链接
        /// </summary>
        public static ConnectionMultiplexer GetRedisConn
        {
            get
            {
                if (_redisConn == null)
                {
                    lock (Locker)
                    {
                        if (_redisConn == null || !_redisConn.IsConnected)
                        {
                            _redisConn = ConnectionMultiplexer.Connect(ConfigurationOptions);
                        }
                    }
                }
                return _redisConn;
            }
        }
    }

        /// <summary>
        /// 生成规则：时间+redis自增
        /// 缺点：能够根据redis自增知道订单量
        /// </summary>
        public static string CreateByRedis()
        {
            //单例获取Redis链接
            var redis = RedisConnection.GetRedisConn;
            var db = redis.GetDatabase();
            //根据当前日期获取Redis订单号自增的key
            var incrkey = "Incr_" + DateTime.Now.ToString("yyyyMMdd");
            if (!db.KeyExists(incrkey))
            {
                db.StringSet(incrkey, 1,new TimeSpan(24,0,0));
            }

            var orderDateTime = DateTime.Now.ToString("yyMMddHHmmssfff");
            var orderIncr = db.StringIncrement(incrkey).ToString("0000000");
            return orderDateTime + orderIncr;
        }