public partial class Form1 : Form     {         string path = @"F:\学习文件";//递归查找树状目录         public Form1()         {递归查找树状目录             InitializeComponent();         }         private void Form1_Load(object sender, EventArgs e)         {             LoadTree(path);         }  public void LoadTree(string path, TreeNode node=null)         {            string[] dirs = Directory.GetDirectories(path);//获取子目录             foreach (string dir in dirs)             {                   TreeNode node1 = new TreeNode(Path.GetFileName(dir));                 //TreeNode node1 = new TreeNode(dir);//文件所有路径                 if (node == null)                 {                     treeView1.Nodes.Add(node1);                 }                 else                 {                     node.Nodes.Add(node1);                 }  if (Directory.GetDirectories(dir).Length > 0)                 {                     LoadTree(dir, node1);                 }             }         }     } }