MARKUS

        /// <param name="Find">T와 동일한 첫번째 Item을 찾는다. 없으면 null을 반환</param>

        public static T Find<T>(this IEnumerable<T> enumerable, Func<T, bool> where) where T : class

        {

            T result = null;

            foreach (var item in enumerable)

            {

                if (where(item))

                {

                    result = item;

                }

            }

            return result;

        }

            /// <summary>

            /// Update all elements of IEnumerable by the update function (only works with reference types)

            /// where the where function returns true

            /// </summary>

            /// <param name="enumerable">The enumerable where you want to change stuff</param>

            /// <param name="update">The way you want to change the stuff</param>

            /// <param name="where">The function to check where updates should be made</param>

            /// <returns>

            /// The same enumerable you passed in

            /// </returns>

            public static IEnumerable<T> UpdateWhere<T>(this IEnumerable<T> enumerable,