递归生成树

 1        public void PopulateTreeView(string directoryValue, TreeNode parentNode)
 2        {
 3            string[] directoryArray = Directory.GetDirectories(directoryValue);
 4            try
 5            {
 6                if (directoryArray.Length != 0)
 7                {
 8                    foreach (string directory in directoryArray)
 9                    {
                        TreeNode myNode = new TreeNode(directory);
                        parentNode.Nodes.Add(myNode);
                        PopulateTreeView(directory, myNode);
                    }
                } 
            }
            catch (UnauthorizedAccessException)
            {
                parentNode.Nodes.Add("Access denied");
            }
        }