Gist 1 from article Autocomplete functionality using prefix trees

Prefix tree autocomplete functionality part 1

private List<string> subsequentStrings;

        /// <summary>
        /// Create a prefix tree - the root node should always store ' '
        /// Initializae the list that will store the strings 
        /// found during the autocomplete process
        /// </summary>
        public Tree()
        {
            _root = new Node(' ');
            subsequentStrings = new List<string>();
        }