USB设备插入USB接口之后，windows产生设备消息，发往每一个window消息队列，可以从WndProc中获得USB插入或移除消息：
protected override void WndProc(ref Message sysm)
{
const int WM_DEVICECHANGE = 0x219;
const int DBT_DEVICEARRIVAL = 0x8000;
try
{
if(sysm.Msg==WM_DEVICECHANGE)
if (sysm.WParam.ToInt32() == DBT_DEVICEARRIVAL)
{
string[] dirs = Environment.GetLogicalDrives(); //取得所有的盘符
foreach (string dir in dirs)
{
DriveInfo 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 + "\r\n";
PSTR += "磁盘卷标：" + Tdriver.VolumeLabel + "\r\n";
PSTR += "文件系统：" + Tdriver.DriveFormat + "\r\n";
PSTR += "剩余大小：" + Tdriver.AvailableFreeSpace.ToString() + "\r\n";
PSTR += "总体容量：" + Tdriver.TotalSize.ToString() + "\r\n";
MessageBox.Show(PSTR);
}
catch {
MessageBox.Show("error");
}
}
}
}
}
}
catch
{ }
base.WndProc(ref sysm);
通过对dirs的的检测，可以发现哪些是USB盘，用USBPhysic.dll可以读取到USB设备的物理信息：
[DllImport("USBPhysic")]
public static extern int Init(string sUser, string sRegCode);
[DllImport("USBPhysic")]
public static extern int GetUSBPhysicInfo(int diskIndex, int InfoType, StringBuilder pHddInfo);
以上是引用USBPhysic.dll中的两个方法，当然Init方法用来注册USBPhysic.dll，之后可以读取到设备信息：
private void Form1_Load(object sender, EventArgs e)
{
string Pstr = "";
StringBuilder T = new StringBuilder();
int A = Init("Mndsoft.com", "C88C-7F7A-725B");
Pstr += "磁盘总数：" + A.ToString() + "\r\n";
A = GetUSBPhysicInfo(0, 0, T);
Pstr += "磁盘串号：" + T.ToString() + "\r\n";
A = GetUSBPhysicInfo(0, 1, T);
Pstr += "磁盘名称：" + T.ToString() + "\r\n";
A = GetUSBPhysicInfo(0, 2, T);
Pstr += "磁盘厂商：" + T.ToString() + "\r\n";
MessageBox.Show(Pstr);
}
上面默认读取0号磁盘信息，对于一个示例U盘，返回如下：
