Develop Reference

Cannot implement USB Detection in .NET Framework using WMI API

I am trying to implement the code from the following link: Detecting USB drive insertion and removal using windows service and c#
I think the issue I am having is that my main UI thread isn't being notified by the background thread when the device is inserted or removed. I verified this by not being able to update the content of a label in my user control.
I have included my source code below:
private void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
MessageBox.Show(property.Name + " = " + property.Value); // Dialog box appears as expected.
StatusMessage.Content = $"{property.Name} = {property.Value}";
}
StatusMessage.Content = "Removable Drive detected!"; //label content should be updated here, and for some reason it is not.
bool isDriveRemoved = FindRemovableDrive(); //get the drive info
if (isDriveRemoved || Count > 0)
{
Count = 0;
}
else
{
Count++;
}
}
private void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
MessageBox.Show(property.Name + " = " + property.Value); // Dialog box appears as expected, but label is not updated.
}
StatusMessage.Content = $"{property.Name} = {property.Value}";
FileMenu.Items.Clear(); // the file menu should be getting cleared here.
}
private void backgroundWorker1_DoWork(object sender, RoutedEventArgs e)
{
WqlEventQuery insertQuery = new WqlEventQuery("SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += DeviceInsertedEvent;
insertWatcher.Start();
WqlEventQuery removeQuery = new WqlEventQuery("SELECT * FROM __InstanceDeletionEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += DeviceRemovedEvent;
removeWatcher.Start();
// Do something while waiting for events
//Thread.Sleep(10000);
}
-Any input/solutions would be greatly appreciated.
Thanks for your time,
Michael

Rather than regularly scanning devices you can use a WMI Events to be notified when there is a hardware change.
Starting a listener for plug & play events:
var wmiPath = new ManagementPath(#"root\cimv2");
var scope = new ManagementScope(wmiPath);
scope.Connect();
var instanceQuery = new WqlEventQuery("__InstanceOperationEvent",
new TimeSpan(0, 0, 1),
"TargetInstance isa \"Win32_PnPEntity\"");
wmiWatcher = new ManagementEventWatcher(scope, instanceQuery);
wmiWatcher.EventArrived += OnInstanceEvent;
wmiWatcher.Start();
The event handler:
private void OnInstanceEvent(object sender, EventArrivedEventArgs ea) {
var eventType = (string)ea.NewEvent["__CLASS"];
var targetWmiObj = ea.NewEvent["TargetInstance"] as ManagementBaseObject;
var deviceId = (string)targetWmiObj["deviceId"];
if (String.Equals("__InstanceCreationEvent", (string)ea.NewEvent["__CLASS"], StringComparison.Ordinal)) {
if (/* Filter on the device id for what is interesting here*/) {
// Handle relevant device arriving
}
}
}
There are other values of NewEvent["__CLASS"] for other event types (including device removal).
PS. This is (partial) code from a WinForms app that monitored for a specialised device being plagged in and then downloaded/uploaded data from it. All the work was done in the thread pool: everything here should just work under WPF.

Get Vendor Id/Manufacturer of the attached USB device in C#

I am working on a C# application. My requirement is that I have to detect (trigger an event) whenever a USB device gets connected to the PC and pass that connected port to another event if the attached device Vendor Id/Manufacturer is "FTDI".
My code for this is:
public class usbState
{
public static List<string> exisitngComPorts = new List<string>();
public event EventHandler<MyEventArgs> DeviceAttached;
public event EventHandler<MyEventArgs> DeviceRemoved;
public usbState()
{
}
private void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
Console.WriteLine(property.Name + " = " + property.Value);
}
string[] newlyAddedComPorts = SerialPort.GetPortNames();
string[] result = newlyAddedComPorts.Except(exisitngComPorts).ToArray();
exisitngComPorts.Add(result[0]);
}
private void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
Console.WriteLine(property.Name + " = " + property.Value);
}
string[] newlyRemovedComPorts = SerialPort.GetPortNames();
string[] result = exisitngComPorts.Except(newlyRemovedComPorts).ToArray();
exisitngComPorts.Remove(result[0]);
}
public void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
WqlEventQuery insertQuery = new WqlEventQuery("SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += new EventArrivedEventHandler(DeviceInsertedEvent);
insertWatcher.Start();
WqlEventQuery removeQuery = new WqlEventQuery("SELECT * FROM __InstanceDeletionEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += new EventArrivedEventHandler(DeviceRemovedEvent);
removeWatcher.Start();
// Do something while waiting for events
System.Threading.Thread.Sleep(20000000);
}
}
The code above does detect whenever a new device gets connected, but I am unable to get the Vendor Id/Manufacturer information, this information can be obtained from "ManagementObject" but the Device Id or PnpDeviceId returned by "ManagementBaseObject" and "ManagementObject" are different. How can I obtain the Vendor Id/Manufacturer information. The information which I am looking for is available in Device Manager, see below image.
How can I obtain this information from my existing code.

I have managed to do it my using ManagementObjectCollection. I did two comparisons, first, attached port with the port given my ManagementObject and second, "Manufacturer" given my ManagementObject with FTDI.
The code is:
public class FtdiDevice
{
public string ComPortName { get; set; }
}
public class usbState
{
public static List<FtdiDevice> existingFtdiPorts = new List<FtdiDevice>();
public static List<string> allComPorts = new List<string>();
public event EventHandler<MyEventArgs> DeviceAttached;
public event EventHandler<MyEventArgs> DeviceRemoved;
public usbState()
{
}
private void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
string[] updatedAddedComPorts = SerialPort.GetPortNames();
string[] result = updatedAddedComPorts.Except(allComPorts).ToArray();
allComPorts.Add(result[0]);
ManagementObjectCollection ManObjReturn;
ManagementObjectSearcher ManObjSearch;
ManObjSearch = new ManagementObjectSearcher("SELECT * FROM Win32_PnPEntity WHERE ClassGuid=\"{4d36e978-e325-11ce-bfc1-08002be10318}\"");
ManObjReturn = ManObjSearch.Get();
foreach (ManagementObject ManObj in ManObjReturn)
{
int s = ManObj.Properties.Count;
string name = ManObj["Name"].ToString();
string man = ManObj["Manufacturer"].ToString();
if (string.Equals(man, "FTDI") && name.Contains(result[0]))
{
existingFtdiPorts.Add(new FtdiDevice() { ComPortName = result[0] });
DeviceAttached(this, new MyEventArgs() { ComPort = result[0] });
break;
}
}
}
private void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
string[] updatedRemovedComPorts = SerialPort.GetPortNames();
string[] result = allComPorts.Except(updatedRemovedComPorts).ToArray();
allComPorts.Remove(result[0]);
var item = existingFtdiPorts.Find(x => x.ComPortName == result[0]);
if (item != null)
{
existingFtdiPorts.Remove(item);
DeviceRemoved(this, new MyEventArgs() { ComPort = result[0] });
}
}
public void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
WqlEventQuery insertQuery = new WqlEventQuery("SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += new EventArrivedEventHandler(DeviceInsertedEvent);
insertWatcher.Start();
WqlEventQuery removeQuery = new WqlEventQuery("SELECT * FROM __InstanceDeletionEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += new EventArrivedEventHandler(DeviceRemovedEvent);
removeWatcher.Start();
// Do something while waiting for events
System.Threading.Thread.Sleep(20000000);
}
}
class Program
{
static void NewDeviceAdded(object source, MyEventArgs e)
{
Console.WriteLine("New Device Attached at Port : " + e.ComPort);
}
static void DeviceRemoved(object source, MyEventArgs e)
{
Console.WriteLine("Device Removed at Port : " + e.ComPort);
}
static void Main(string[] args)
{
usbState.allComPorts = SerialPort.GetPortNames().ToList();
usbState usb = new usbState();
usb.DeviceAttached += NewDeviceAdded;
usb.DeviceRemoved += DeviceRemoved;
ManagementObjectCollection ManObjReturn;
ManagementObjectSearcher ManObjSearch;
ManObjSearch = new ManagementObjectSearcher("SELECT * FROM Win32_PnPEntity WHERE ClassGuid=\"{4d36e978-e325-11ce-bfc1-08002be10318}\"");
ManObjReturn = ManObjSearch.Get();
foreach (ManagementObject ManObj in ManObjReturn)
{
for(int x = 0; x < usbState.allComPorts.Count; x++)
{
string name = ManObj["Name"].ToString();
string man = ManObj["Manufacturer"].ToString();
if (string.Equals(man, "FTDI") && name.Contains(usbState.allComPorts[x]))
{
usbState.existingFtdiPorts.Add(new FtdiDevice() { ComPortName = usbState.allComPorts[x] });
break;
}
}
}
BackgroundWorker bgwDriveDetector = new BackgroundWorker();
bgwDriveDetector.DoWork += usb.backgroundWorker1_DoWork;
bgwDriveDetector.RunWorkerAsync();
bgwDriveDetector.WorkerReportsProgress = true;
bgwDriveDetector.WorkerSupportsCancellation = true;
// System.Threading.Thread.Sleep(100000);
Console.ReadKey();
}
}
MyEventArgs class is:
public class MyEventArgs : EventArgs
{
public string ComPort { get; set; }
}

C# backgroundworker & eventhandler together - searching USB devices

I am first time using BackGroundWorker and EventHandler. I dont know if I am doing it correctly or not. I want to search for USB devices connected (just which have certain VID & PID). Because by debugging program dont want to go inside bw_worker_dowork loop.
I also using WPF with MVVM method - for info.
Please for help. I am doing it correctly or not?
BackgroundWorker bw_worker;
USBmiddleware cs = new USBmiddleware();
public Windows1ViewModel()
{
bw_worker = new BackgroundWorker();
bw_worker.DoWork += new DoWorkEventHandler(bw_worker_dowork);
bw_worker.WorkerReportsProgress = true;
bw_worker.WorkerReportsProgress = true;
}
void bw_worker_dowork(object sender, DoWorkEventArgs e)
{
WqlEventQuery insertQuery = new WqlEventQuery("SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += new EventArrivedEventHandler(DeviceInsertedEvent);
insertWatcher.Start();
WqlEventQuery removeQuery = new WqlEventQuery("SELECT * FROM __InstanceDeletionEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += new EventArrivedEventHandler(DeviceRemovedEvent);
removeWatcher.Start();
// Do something while waiting for events
System.Threading.Thread.Sleep(20000000);
}
void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
cs.FindDevices();
}
void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
cs.FindDevices();
}

You didn't start your BackgroundWorker !
BackgroundWorker.RunWorkerAsync Method

Sorry. Problem was there:
Before:
"SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'"
Now:
"SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 2"
Before was working only on my USB Headset, now working also for my other device :) Sorry.

.NET Events for Process executable start

Is there any way to register for an event that fires when an executable of a particular filename starts? I know it's easy enough to get an event when a process exits, by getting the process handle and registering for the exited event. But how can you be notified when a process, that isn't already running, starts...without polling all the running processes?

You could use the following:
private ManagementEventWatcher WatchForProcessStart(string processName)
{
string queryString =
"SELECT TargetInstance" +
" FROM __InstanceCreationEvent " +
"WITHIN 10 " +
" WHERE TargetInstance ISA 'Win32_Process' " +
" AND TargetInstance.Name = '" + processName + "'";
// The dot in the scope means use the current machine
string scope = #"\\.\root\CIMV2";
// Create a watcher and listen for events
ManagementEventWatcher watcher = new ManagementEventWatcher(scope, queryString);
watcher.EventArrived += ProcessStarted;
watcher.Start();
return watcher;
}
private ManagementEventWatcher WatchForProcessEnd(string processName)
{
string queryString =
"SELECT TargetInstance" +
" FROM __InstanceDeletionEvent " +
"WITHIN 10 " +
" WHERE TargetInstance ISA 'Win32_Process' " +
" AND TargetInstance.Name = '" + processName + "'";
// The dot in the scope means use the current machine
string scope = #"\\.\root\CIMV2";
// Create a watcher and listen for events
ManagementEventWatcher watcher = new ManagementEventWatcher(scope, queryString);
watcher.EventArrived += ProcessEnded;
watcher.Start();
return watcher;
}
private void ProcessEnded(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject targetInstance = (ManagementBaseObject) e.NewEvent.Properties["TargetInstance"].Value;
string processName = targetInstance.Properties["Name"].Value.ToString();
Console.WriteLine(String.Format("{0} process ended", processName));
}
private void ProcessStarted(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject targetInstance = (ManagementBaseObject)e.NewEvent.Properties["TargetInstance"].Value;
string processName = targetInstance.Properties["Name"].Value.ToString();
Console.WriteLine(String.Format("{0} process started", processName));
}
You would then call either WatchForProcessStart and/or WatchForProcessEnd passing in your process name (eg "notepad.exe").
The ManagementEventWatcher object is returned from the two Watch* methods as it implements IDisposable and so you should call Dispose on these objects when you have finished with them to prevent issues.
You could also change the polling value in the queries if you need the event to be raised more quickly after the process has started. To do this change the line "WITHIN 10" to be WITHIN something less than 10.

WMI can create events when processes are created. You could then filter these events.

Here is code.
Notice that you have to start Visual Studio like Administrator in order to execute this code.
using System;
using System.Management;
namespace AppLaunchDetector
{
class Program
{
static void Main(string[] args)
{
ManagementEventWatcher w = null;
WqlEventQuery q;
try
{
q = new WqlEventQuery();
q.EventClassName = "Win32_ProcessStartTrace";
w = new ManagementEventWatcher(q);
w.EventArrived += new EventArrivedEventHandler(ProcessStartEventArrived);
w.Start();
Console.ReadLine(); // block main thread for test purposes
}
catch (Exception ex)
{
}
finally
{
w.Stop();
}
}
static void ProcessStartEventArrived(object sender, EventArrivedEventArgs e)
{
foreach (PropertyData pd in e.NewEvent.Properties)
{
Console.WriteLine("\n============================= =========");
Console.WriteLine("{0},{1},{2}", pd.Name, pd.Type, pd.Value);
}
}
}
}

Detecting USB drive insertion and removal using windows service and c#

Looking into possibility of making an USB distributed application
that will autostart on insertion of an USB stick and shutdown when removing the stick
Will use .Net and C#.
Looking for suggestion how to approach this using C#?
Update: Two possible solutions implementing this as a service.
- override WndProc
or
- using WMI query with ManagementEventWatcher

You can use WMI, it is easy and it works a lot better than WndProc solution with services.
Here is a simple example:
using System.Management;
ManagementEventWatcher watcher = new ManagementEventWatcher();
WqlEventQuery query = new WqlEventQuery("SELECT * FROM Win32_VolumeChangeEvent WHERE EventType = 2");
watcher.EventArrived += new EventArrivedEventHandler(watcher_EventArrived);
watcher.Query = query;
watcher.Start();
watcher.WaitForNextEvent();

This works well for me, plus you can find out more information about the device.
using System.Management;
private void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
Console.WriteLine(property.Name + " = " + property.Value);
}
}
private void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
Console.WriteLine(property.Name + " = " + property.Value);
}
}
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
WqlEventQuery insertQuery = new WqlEventQuery("SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += new EventArrivedEventHandler(DeviceInsertedEvent);
insertWatcher.Start();
WqlEventQuery removeQuery = new WqlEventQuery("SELECT * FROM __InstanceDeletionEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += new EventArrivedEventHandler(DeviceRemovedEvent);
removeWatcher.Start();
// Do something while waiting for events
System.Threading.Thread.Sleep(20000000);
}

Adding to VitalyB's post.
To raise an event where ANY USB device is inserted, use the following:
var watcher = new ManagementEventWatcher();
var query = new WqlEventQuery("SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 2");
watcher.EventArrived += new EventArrivedEventHandler(watcher_EventArrived);
watcher.Query = query;
watcher.Start();
This will raise an event whenever a USB device is plugged. It even works with a National Instruments DAQ that I'm trying to auto-detect.

VitalyB's answer does't cover remove of the device. I changed it a bit to trigger the event both when media is inserted and removed and also code to get the drive letter of the inserted media.
using System;
using System.Management;
namespace MonitorDrives
{
class Program
{
public enum EventType
{
Inserted = 2,
Removed = 3
}
static void Main(string[] args)
{
ManagementEventWatcher watcher = new ManagementEventWatcher();
WqlEventQuery query = new WqlEventQuery("SELECT * FROM Win32_VolumeChangeEvent WHERE EventType = 2 or EventType = 3");
watcher.EventArrived += (s, e) =>
{
string driveName = e.NewEvent.Properties["DriveName"].Value.ToString();
EventType eventType = (EventType)(Convert.ToInt16(e.NewEvent.Properties["EventType"].Value));
string eventName = Enum.GetName(typeof(EventType), eventType);
Console.WriteLine("{0}: {1} {2}", DateTime.Now, driveName, eventName);
};
watcher.Query = query;
watcher.Start();
Console.ReadKey();
}
}
}

A little bit edit on all above answer:
using System.Management;
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
bgwDriveDetector.DoWork += bgwDriveDetector_DoWork;
bgwDriveDetector.RunWorkerAsync();
}
private void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
string driveName = e.NewEvent.Properties["DriveName"].Value.ToString();
MessageBox.Show(driveName + " inserted");
}
private void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
string driveName = e.NewEvent.Properties["DriveName"].Value.ToString();
MessageBox.Show(driveName + " removed");
}
void bgwDriveDetector_DoWork(object sender, DoWorkEventArgs e)
{
var insertQuery = new WqlEventQuery("SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 2");
var insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += DeviceInsertedEvent;
insertWatcher.Start();
var removeQuery = new WqlEventQuery("SELECT * FROM Win32_DeviceChangeEvent WHERE EventType = 3");
var removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += DeviceRemovedEvent;
removeWatcher.Start();
}
}

You can also use WMI to detect insertion events. It's a little bit more complicated than monitoring for WM_CHANGEDEVICE messages, but it does not require a window handle which may be useful if you are running in the background as a service.

Try WM_CHANGEDEVICE handling.

My complete answer can be found here as a gist
I found the answer to determining the drive letter from the serial # from this question/answer
How to get the drive letter of USB device using WMI
And I modified Phil Minor's code to make it reactive:
public class UsbDetector : IUsbDetector
{
private const string Query = "SELECT * FROM {0} WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'";
private const string CreationEvent = "__InstanceCreationEvent";
private const string DeletionEvent = "__InstanceDeletionEvent";
private const int ReplayNumber = 1;
private readonly Subject<USBDeviceInfo> adds = new Subject<USBDeviceInfo>();
private readonly Subject<USBDeviceInfo> removes = new Subject<USBDeviceInfo>();
public UsbDetector()
{
var bgwDriveDetector = new BackgroundWorker();
bgwDriveDetector.DoWork += DoWork;
bgwDriveDetector.RunWorkerAsync();
}
public IObservable<USBDeviceInfo> Adds => adds.AsObservable();
public IObservable<USBDeviceInfo> Removes => removes.AsObservable();
private void DoWork(object sender, DoWorkEventArgs e)
{
SubscribeToEvent(CreationEvent, adds);
SubscribeToEvent(DeletionEvent, removes);
}
private static void SubscribeToEvent(string eventType, IObserver<USBDeviceInfo> observer)
{
WqlEventQuery wqlEventQuery = new WqlEventQuery(string.Format(Query, eventType));
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(wqlEventQuery);
var observable = Observable.FromEventPattern<EventArrivedEventHandler, EventArrivedEventArgs>(
h => insertWatcher.EventArrived += h,
h => insertWatcher.EventArrived -= h).Replay(ReplayNumber);
observable.Connect();
observable.Select(a => a.EventArgs).Select(MapEventArgs).Subscribe(observer);
insertWatcher.Start();
}
private static USBDeviceInfo MapEventArgs(EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
string deviceId = (string)instance.GetPropertyValue("DeviceID");
string serialNr = deviceId.Substring(deviceId.LastIndexOf('\\')).Replace("\\", "");
char driveLetter = GetDriveLetter(serialNr).First();
return new USBDeviceInfo(deviceId, serialNr, driveLetter);
}

Here is what we did with C# .Net 4.0 under a WPF app. We are still searching for an answer to "how to tell WHICH device type was inserted/removed", but this is a start:
using System.Windows.Interop;
...
public partial class MainWindow : Window
{
...
public MainWindow()
{
...
}
//============================================================
// WINDOWS MESSAGE HANDLERS
//
private const int WM_DEVICECHANGE = 0x0219; // int = 537
private const int DEVICE_NOTIFY_ALL_INTERFACE_CLASSES = 0x00000004;
/// <summary>
///
/// </summary>
/// <param name="e"></param>
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
source.AddHook(WndProc);
}
private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
if (msg == WM_DEVICECHANGE)
{
ReadDongleHeader();
}
return IntPtr.Zero;
}
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Management;
using System.ComponentModel;
namespace ConsoleApplication4
{
public class usbState
{
public usbState()
{
}
private void DeviceInsertedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
Console.WriteLine(property.Name + " = " + property.Value);
}
}
private void DeviceRemovedEvent(object sender, EventArrivedEventArgs e)
{
ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
foreach (var property in instance.Properties)
{
Console.WriteLine(property.Name + " = " + property.Value);
}
}
public void bgwDriveDetector_DoWork(object sender, DoWorkEventArgs e)
{
WqlEventQuery insertQuery = new WqlEventQuery("SELECT * FROM __InstanceCreationEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher insertWatcher = new ManagementEventWatcher(insertQuery);
insertWatcher.EventArrived += new EventArrivedEventHandler(DeviceInsertedEvent);
insertWatcher.Start();
WqlEventQuery removeQuery = new WqlEventQuery("SELECT * FROM __InstanceDeletionEvent WITHIN 2 WHERE TargetInstance ISA 'Win32_USBHub'");
ManagementEventWatcher removeWatcher = new ManagementEventWatcher(removeQuery);
removeWatcher.EventArrived += new EventArrivedEventHandler(DeviceRemovedEvent);
removeWatcher.Start();
}
}
class Class1
{
private static void Main(string[] args)
{
usbState usb= new usbState();
BackgroundWorker bgwDriveDetector = new BackgroundWorker();
bgwDriveDetector.DoWork += usb.bgwDriveDetector_DoWork;
bgwDriveDetector.RunWorkerAsync();
bgwDriveDetector.WorkerReportsProgress = true;
bgwDriveDetector.WorkerSupportsCancellation = true;
// System.Threading.Thread.Sleep(100000);
Console.ReadKey();
}
}
}