c#生成类似Mongodb的ObjectId有序、不重复Guid

private static DateTime dt1970 = new DateTime(1970, 1, 1);
private static Random rnd = new Random();
private static readonly int __staticMachine = ((0x00ffffff & Environment.MachineName.GetHashCode()) +
#if NETSTANDARD1_5 || NETSTANDARD1_6
    1
#else
    AppDomain.CurrentDomain.Id
#endif
    ) & 0x00ffffff;
private static readonly int __staticPid = Process.GetCurrentProcess().Id;
private static int __staticIncrement = rnd.Next();
/// <summary>
/// 生成类似Mongodb的ObjectId有序、不重复Guid
/// </summary>
/// <returns></returns>
public static Guid NewMongodbId() {
    var now = DateTime.Now;
    var uninxtime = (int) now.Subtract(dt1970).TotalSeconds;
    int increment = Interlocked.Increment(ref __staticIncrement) & 0x00ffffff;
    var rand = rnd.Next(0, int.MaxValue);
    var guid = $"{uninxtime.ToString("x8").PadLeft(8, '0')}{__staticMachine.ToString("x8").PadLeft(8, '0').Substring(2, 6)}{__staticPid.ToString("x8").PadLeft(8, '0').Substring(6, 2)}{increment.ToString("x8").PadLeft(8, '0')}{rand.ToString("x8").PadLeft(8, '0')}";
    return Guid.Parse(guid);
}
 
//代码来自 dotnetGen
//https://github.com/2881099/dotnetGen_postgresql
//https://github.com/2881099/dotnetGen_mysql
//https://github.com/2881099/dotnetGen_sqlserver