using System;

using System.Text;

using System.Security.Cryptography;

​

public class Program

{

    public static void Main()

    {

        UseAHash();

        UseTime();

    }

​

    public static void UseAHash()

    {

        var primaryKey = 123345;

        HashAlgorithm algorithm = SHA1.Create();

        var hash = algorithm.ComputeHash(Encoding.UTF8.GetBytes(primaryKey.ToString()));

        StringBuilder sb = new StringBuilder();

        for (var i = 0; i < 6; ++i)

        {

            sb.Append(hash[i].ToString("X2"));

        }

​

        Console.WriteLine(sb);

    }

​

    public static void UseTime()

    {

        StringBuilder builder = new StringBuilder();

        // use universal to avoid daylight to standard time change.

        var now = DateTime.Now.ToUniversalTime();

        builder.Append(now.DayOfYear.ToString("D3"));

        builder.Append(now.Hour.ToString("D2"));

        builder.Append(now.Minute.ToString("D2"));

        builder.Append(now.Second.ToString("D2"));

        builder.Append(now.Millisecond.ToString("D3"));

        Console.WriteLine("Length: " + builder.Length);

        Console.WriteLine("Result: " + builder);

    }

}