C# - HashableElement

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using System.Security.Cryptography;

namespace DotNetSnippets
{
    internal class MD5Ignore : System.Attribute
    {
    }
    
    internal class HashableElement
    {
        private Guid id;
        private DateTime creation;
        private string user;
        private string currentValue;
        private Version version;

        public HashableElement()
        {

        }
        /// <summary>
        /// Beschreibung: 
        /// </summary>
        [MD5Ignore]
        public Version Version
        {
            get
            {
                return version;
            }
            set
            {
                version = value;
            }
        }
	

        /// <summary>
        /// Beschreibung: 
        /// </summary>
        public string Value
        {
            get
            {
                return currentValue;
            }
            set
            {
                currentValue = value;
            }
        }
	

        /// <summary>
        /// Beschreibung: 
        /// </summary>
        public string User
        {
            get
            {
                return user;
            }
            set
            {
                user = value;
            }
        }
	

        /// <summary>
        /// Beschreibung: 
        /// </summary>
        public DateTime Creation
        {
            get
            {
                return creation;
            }
            set
            {
                creation = value;
            }
        }
	

        /// <summary>
        /// Beschreibung: 
        /// </summary>
        public Guid Id
        {
            get
            {
                return id;
            }
            set
            {
                id = value;
            }
        }

        internal string GetCheckSum()
        {
            List<PropertyInfo> properties = new List<PropertyInfo>(this.GetType().GetProperties());
            List<PropertyInfo> validProperties = new List<PropertyInfo>(properties.FindAll(delegate(PropertyInfo any)
            {
                return (any.GetCustomAttributes(typeof(MD5Ignore), true).Length == 0);
            }));
            string checkSumBase = string.Empty;
            foreach (PropertyInfo pInfo in validProperties)
            {
                checkSumBase += String.Format("{0} / ",pInfo.GetValue(this, null).ToString());
            }



            byte[] data = MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(checkSumBase));

            StringBuilder sBuilder = new StringBuilder();

            for (int i = 0; i < data.Length; i++)
            {
                sBuilder.Append(data[i].ToString("x2"));
            }

            return sBuilder.ToString();
      
         

        }

        private string GetMd5Salt()
        {
            return "exampleSalt";
        }
	
    }
}