using System;

using System.Security.Cryptography;

using System.Text;

using System.Runtime.InteropServices;

​

public class Program

{

    public static void Main()

    {

        string itemid = "008809";

        decimal listprice = 17.79M;

        decimal ppcprice = 7.0M;

        string offerId = "ON231220274";

        string input = listprice.ToString("0.00") + "|" + ppcprice.ToString("0.00");

        if (!string.IsNullOrEmpty(offerId))

            input = input + "|" + offerId;

        Console.WriteLine("input: " + input);

        Console.WriteLine("");

        var uniqueid = GenerateEntityUniqueId(input);

        var uniqueid2 = CreateMd5Deterministic(input);

        Console.WriteLine("SHA5 generated ID: " + uniqueid);

        Console.WriteLine("MD5 generated ID: " + uniqueid2);

    }

​

    public static Guid GenerateEntityUniqueId(string input)

    {

        if (string.IsNullOrEmpty(input))

        {

            throw new ArgumentNullException("input");

        }

​

        using (SHA256 sHA = SHA256.Create())

        {

            string s = input.ToUpperInvariant();

            byte[] bytes = Encoding.UTF8.GetBytes(s);

            byte[] array = sHA.ComputeHash(bytes);

            Array.Resize(ref array, 16);

            return new Guid(array);

        }

    }

​

    public static Guid CreateMd5Deterministic(ReadOnlySpan<char> input)

    {

        var byteSpan = MemoryMarshal.AsBytes(input);

        Span<byte> hash = MD5.HashData(byteSpan);

        var guid = new Guid(hash);

        return guid;

    }

}