Enum Mapper in C#

EnumMapper.cs

	public class EnumMapper : IDisposable
	{
		readonly Dictionary<Type, Dictionary<string, object>> _stringsToEnums =
			new Dictionary<Type, Dictionary<string, object>>( ) ;

		readonly Dictionary<Type, Dictionary<int, string>> _enumNumbersToStrings =
			new Dictionary<Type, Dictionary<int, string>>( ) ;

		readonly ReaderWriterLockSlim _lock = new ReaderWriterLockSlim( ) ;

		public object EnumFromString( Type type, string value )
		{
			populateIfNotPresent( type ) ;

			return _stringsToEnums[ type ][ value ] ;
		}

		public string StringFromEnum( object theEnum )
		{
			Type typeOfEnum = theEnum.GetType( ) ;

			populateIfNotPresent( typeOfEnum ) ;

			return _enumNumbersToStrings[ typeOfEnum ][ (int) theEnum ] ;
		}

		void populateIfNotPresent( Type type )
		{
			_lock.EnterUpgradeableReadLock( ) ;
			try
			{
				if( !_stringsToEnums.ContainsKey( type ) )
				{
					_lock.EnterWriteLock( ) ;
					try
					{
						populate( type ) ;
					}
					finally
					{
						_lock.ExitWriteLock( ) ;
					}
				}
			}
			finally
			{
				_lock.ExitUpgradeableReadLock( ) ;
			}
		}

		void populate( Type type )
		{
			Array values = Enum.GetValues( type ) ;
			_stringsToEnums[ type ] = new Dictionary<string, object>( values.Length ) ;
			_enumNumbersToStrings[ type ] = new Dictionary<int, string>( values.Length ) ;

			for( int i = 0; i < values.Length; i++ )
			{
				object value = values.GetValue( i ) ;
				_stringsToEnums[ type ].Add( value.ToString( ), value ) ;
				_enumNumbersToStrings[ type ].Add( (int) value, value.ToString( ) ) ;
			}
		}

		public void Dispose( )
		{
			_lock.Dispose( ) ;
		}
	}
}

Sorry for the delay in putting the license info there - I didn't see the e-mail alerts.