下面我通过一个小例子并结合一段代码片段给大家展示下，有需要的朋友可以来借鉴下。

界面上拖一个 button 和treeview ，运行的时候直接插入优盘，单机按钮就会出现目录文件。不过只能在u盘插入，U盘拔出时，才能接收到信息。

1.[C#]代码

using System; using System.Collections; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.IO; using System.Linq; using System.Text; using System.Threading; using System.Threading.Tasks; using System.Windows.Forms; namespace usbText { public partial class Form1 : Form { DriveInfo Tdriver = null; public Form1() { InitializeComponent(); } protected override void WndProc(ref Message m) { if (m.Msg == 0x0219)//WM_DEVICECHANGE { switch (m.WParam.ToInt32()) { case 0x8000://DBT_DEVICEARRIVAL { MessageBox.Show("设备插入"); string[] dirs = Environment.GetLogicalDrives(); //取得所有的盘符 foreach (string dir in dirs) { Tdriver = new DriveInfo(dir); if (Tdriver.DriveType == DriveType.Removable) { { while (Tdriver.IsReady == false) { Thread.Sleep(500); } try { string PSTR = ""; PSTR += "磁盘名称：" + Tdriver.Name + "rn"; PSTR += "磁盘卷标：" + Tdriver.VolumeLabel + "rn"; PSTR += "文件系统：" + Tdriver.DriveFormat + "rn"; PSTR += "剩余大小：" + Tdriver.AvailableFreeSpace.ToString() + "rn"; PSTR += "总体容量：" + Tdriver.TotalSize.ToString() + "rn"; PSTR += "总体容量：" + Tdriver.RootDirectory.ToString() + "rn"; MessageBox.Show(PSTR); } catch { MessageBox.Show("error"); } } } } break; } case 0x8004://DBT_DEVICEREMOVECOMPLETE { MessageBox.Show("设备拔出"); break; } } } base.WndProc(ref m); } private void AddToTreeView(TreeNode node) { treeView1.Nodes.Add(node); treeView1.Refresh(); } internal void LoadFolderFileList(string path, TreeNode nodes) { string[] dirs = Directory.GetDirectories(path); string[] files = Directory.GetFiles(path); for (int i = 0; i < dirs.Length; i++) { string[] info = new string[4]; DirectoryInfo di = new DirectoryInfo(dirs[i]); TreeNode node = new TreeNode(di.Name); node.Tag = di.FullName; try { if (di.GetDirectories().Length > 0 || di.GetFiles().Length > 0) { LoadFolderFileList(di.FullName, node); } else { continue; } } catch { continue; } nodes.Nodes.Add(node); } for (int i = 0; i < files.Length; i++) { FileInfo fi = new FileInfo(files[i]); TreeNode node = new TreeNode(fi.Name); node.Tag = fi.FullName; nodes.Nodes.Add(node); } } private void button1_Click(object sender, EventArgs e) { if (Tdriver != null) { TreeNode node = new TreeNode(); LoadFolderFileList(Tdriver.RootDirectory.ToString(), node); treeView1.Nodes.Add(node); } } } }

通过以上代码可以实现打开并读取usb的文件目录，希望大家能够喜欢。