检测U盘

    public partial class Form1 : Form
    {
        public const int WM_DEVICECHANGE = 0x219;
        public const int DBT_DEVICEARRIVAL = 0x8000;
        public const int DBT_CONFIGCHANGECANCELED = 0x0019;
        public const int DBT_CONFIGCHANGED = 0x0018;
        public const int DBT_CUSTOMEVENT = 0x8006;
        public const int DBT_DEVICEQUERYREMOVE = 0x8001;
        public const int DBT_DEVICEQUERYREMOVEFAILED = 0x8002;
        public const int DBT_DEVICEREMOVECOMPLETE = 0x8004;
        public const int DBT_DEVICEREMOVEPENDING = 0x8003;
        public const int DBT_DEVICETYPESPECIFIC = 0x8005;
        public const int DBT_DEVNODES_CHANGED = 0x0007;
        public const int DBT_QUERYCHANGECONFIG = 0x0017;
        public const int DBT_USERDEFINED = 0xFFFF;

        public Form1()
        {
            InitializeComponent();
        }

        protected override void WndProc(ref Message m)
        {
            if (m.Msg == WM_DEVICECHANGE)
            {
                StringBuilder str = new StringBuilder();
                switch (m.WParam.ToInt32())
                {

                    case DBT_DEVNODES_CHANGED:
                        DriveInfo[] drivers = DriveInfo.GetDrives();
                        foreach (DriveInfo info in drivers)
                        {
                            if (info.DriveType == DriveType.Removable)
                            {
                                str.Append("盘符：" + info.Name);
                            }
                        }
                        MessageBox.Show(str.ToString());

                        break;
                }
            }

            base.WndProc(ref m);
        }
    }