根据SQL Server排序规则创建顺序GUID

 public static class GuidUtil
    {
        private static readonly long EpochMilliseconds = new DateTime(, , , , , , DateTimeKind.Utc).Ticks / 10000L;

        /// <summary>
        /// Creates a sequential GUID according to SQL Server's ordering rules.
        /// </summary>
        public static Guid NewSequentialId()
        {
            // This code was not reviewed to guarantee uniqueness under most conditions, nor completely optimize for avoiding
            // page splits in SQL Server when doing inserts from multiple hosts, so do not re-use in production systems.
            var guidBytes = Guid.NewGuid().ToByteArray();

            // get the milliseconds since Jan 1 1970
            byte[] sequential = BitConverter.GetBytes((DateTime.Now.Ticks / 10000L) - EpochMilliseconds);

            // discard the 2 most significant bytes, as we only care about the milliseconds increasing, but the highest ones
            // should be 0 for several thousand years to come (non-issue).
            if (BitConverter.IsLittleEndian)
            {
                guidBytes[] = sequential[];
                guidBytes[] = sequential[];
                guidBytes[] = sequential[];
                guidBytes[] = sequential[];
                guidBytes[] = sequential[];
                guidBytes[] = sequential[];
            }
            else
            {
                Buffer.BlockCopy(sequential, , guidBytes, , );
            }

            return new Guid(guidBytes);
        }
    }