Database Raise Error exception converter

DatabaseExceptionConverter.cs

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Reflection;
using System.Text.RegularExpressions;

namespace Utilities.Database
{
    /// <summary>
    /// Converts exceptions thrown by the DB into the correct exception
    /// 
    /// Original code by Nuno Lourenço @ F6 Portugal
    /// </summary>
    public static class DatabaseExceptionConverter
    {
        /// <summary>
        /// Defines the format of the database exception messages
        /// </summary>
        private static readonly Regex dbExceptionExpression = new Regex(@"^(?<exception>\w+Exception\s*)\s*:?\s*(?<message>.*)$", RegexOptions.Singleline | RegexOptions.Compiled);

        private static readonly IDictionary<string, Type> availableExceptions = InitAvailableExceptions();
        
        private static IDictionary<string, Type> InitAvailableExceptions()
        {
            IDictionary<string, Type> ret = new Dictionary<string, Type>();
            foreach (Type exception in Assembly.GetExecutingAssembly().GetTypes())
            {
                if (typeof(Exception).IsAssignableFrom(exception))
                {
                    ret.Add(exception.Name, exception);
                }
            }
            return ret;
        }


        private static IDictionary<string, Type> AvailableExceptions
        {
            get { return availableExceptions; }
        }

        /// <summary>
        /// Converts the SqlException to known exception
        /// </summary>
        /// <remarks>
        /// It is an error to pass an exception with a message that is matched by <see cref="dbExceptionExpression" />
        /// but for which there is no corresponding exception
        /// </remarks>
        /// <param name="exception">The exception.</param>
        /// <returns>Returns an exception of the type defined in the exception message.</returns>
        public static Exception Convert(SqlException exception)
        {
            // Check the exception message for a match
            Match match = dbExceptionExpression.Match(exception.Message);
            if (!match.Success)
                return exception;

            string exceptionTypeName = match.Groups["exception"].Value;
            string exceptionMessage = match.Groups["message"].Value;

            Type exceptionType = GetExceptionType(exceptionTypeName);

            if (exceptionType != null)
                return (Exception)Activator.CreateInstance(exceptionType, exceptionMessage, exception);
            
            return exception;
        }

        /// <summary>
        /// Gets the type of the exception from the specified name.
        /// </summary>
        /// <param name="exceptionTypeName">Name of the exception's type.</param>
        /// <returns></returns>
        private static Type GetExceptionType(string exceptionTypeName)
        {
            if (AvailableExceptions.ContainsKey(exceptionTypeName))
                return AvailableExceptions[exceptionTypeName];
            
            return null;
        }
    }
}