Develop Reference

C# how to effectively detect which graphic card is used [duplicate]

My C# application sits on the embedded box which has Intel motherboard and graphics chipset. ATI graphics card is put on to PCI express. Generally graphics card drives the video, but if ATI card fails then the video comes out from graphics chipset.
I have to detect the failure of ATI graphics card for diagnostic purposes.
Any ideas/sample code on how to do this.
Thanks in advance
Raju

This should hopefully get you started.
Add a reference to System.Management, then you can do this:
ManagementObjectSearcher searcher
= new ManagementObjectSearcher("SELECT * FROM Win32_DisplayConfiguration");
string graphicsCard = string.Empty;
foreach (ManagementObject mo in searcher.Get())
{
foreach (PropertyData property in mo.Properties)
{
if (property.Name == "Description")
{
graphicsCard = property.Value.ToString();
}
}
}
In my case, graphicsCard is equal to
NVIDIA GeForce 8400 GS (Microsoft
Corporation - WDDM v1.1)

I'm not a fan of how the selected answer only returns the first video controller. Also, there's no need to loop over all the properties. Just get the ones you need. If CurrentBitsPerPixel is not null, then you're looking at one of the active controllers. I'm using Win32_VideoController as suggested by #bairog, instead of the deprecated Win32_DisplayConfiguration.
ManagementObjectSearcher searcher =
new ManagementObjectSearcher("SELECT * FROM Win32_VideoController");
foreach (ManagementObject mo in searcher.Get())
{
PropertyData currentBitsPerPixel = mo.Properties["CurrentBitsPerPixel"];
PropertyData description = mo.Properties["Description"];
if (currentBitsPerPixel != null && description != null)
{
if (currentBitsPerPixel.Value != null)
System.Console.WriteLine(description.Value);
}
}
My machine has 3 video controllers. The first one is not active (ShoreTel). The second one is active, but is not the video card (Desktop Authority). The third one is my NVidia. This code will print out both the DA controller and the NVidia controller.

Promoted answer works only for single video card system. When I have ATI and Nvidia cards - WMI query returns ATI even if that monitor is plugged into Nvidia card, dxdiag shows Nvidia and games runs on that card (usage).
The only way I could determine right video card was using SlimDX to create DX device and examine what card it used. However that .dll weights over 3Mb.
var graphicsCardName = new Direct3D().Adapters[0].Details.Description;

Your question isn't entirely clear, so I'm not sure if the follwing idea will help or not.
Perhaps something very simple would suffice:
If the two graphics cards run different resolutions check the monitor resolution using:
System.Windows.Forms.SystemInformation.PrimaryMonitorSize
Similarly, if one card supports more than one monitor, check the number of monitors using SystemInformation.MonitorCount.

I tried all the approaches in this question but none gives me a correct answer. However I found it possible to get your current using the Win32_DisplayControllerConfiguration class. Although according to MSDN this class is obsolete, it's the only one returning a correct answer:
using System;
using System.Management;
using System.Windows.Forms;
namespace WMISample
{
public class MyWMIQuery
{
public static void Main()
{
try
{
ManagementObjectSearcher searcher =
new ManagementObjectSearcher("root\\CIMV2",
"SELECT * FROM Win32_DisplayControllerConfiguration");
foreach (ManagementObject queryObj in searcher.Get())
{
Console.WriteLine("----------------------------------- ");
Console.WriteLine("Win32_DisplayControllerConfiguration instance");
Console.WriteLine("-----------------------------------");
Console.WriteLine("Name: {0}", queryObj["Name"]);
}
}
catch (ManagementException e)
{
MessageBox.Show("An error occurred while querying for WMI data: " + e.Message);
}
}
}
}
(Code generated by WMI Code Creator, a great tool if you are messing with WMI.)
This gives GeForce GTX 1080 on my Windows 10 (RS2) + Intel(R) HD Graphics 4600 + NVIDIA GeForce GTX 1080 system.

Sometimes I need to switch between the Nvidia GPU and onboard GPU. To know which is connected to the monitor, I use the property MinRefreshRate. It works reliably for me, not CurrentBitsPerPixel.
public static void UpdateActiveGpu()
{
ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT * FROM Win32_VideoController");
foreach (ManagementObject mo in searcher.Get())
{
PropertyData minRefreshRate = mo.Properties["MinRefreshRate"];
PropertyData description = mo.Properties["Description"];
if (minRefreshRate != null && description != null && minRefreshRate.Value != null)
{
Global.Instance.activeGpu = description.Value.ToString();
break;
}
}
}

How do I get same hardware id as in UnityEngine.SystemInfo.deviceUniqueIdentifier?

I want to get the same hardware id in windows forms application that i get when i use UnityEngine.SystemInfo.deviceUniqueIdentifier in my game.
How can I get the same hardware id?

I know I'm late but Unity's SystemInfo::deviceUniqueIdentifier is built like this:
Requires: using System.Management; in System.Management.dll (.NET Framework)
private string GetDeviceUniqueIdentifier() {
string ret = string.Empty;
string concatStr = string.Empty;
try {
using ManagementObjectSearcher searcherBb = new ManagementObjectSearcher("SELECT * FROM Win32_BaseBoard");
foreach (var obj in searcherBb.Get()) {
concatStr += (string)obj.Properties["SerialNumber"].Value ?? string.Empty;
}
using ManagementObjectSearcher searcherBios = new ManagementObjectSearcher("SELECT * FROM Win32_BIOS");
foreach (var obj in searcherBios.Get()) {
concatStr += (string)obj.Properties["SerialNumber"].Value ?? string.Empty;
}
using ManagementObjectSearcher searcherOs = new ManagementObjectSearcher("SELECT * FROM Win32_OperatingSystem");
foreach (var obj in searcherOs.Get()) {
concatStr += (string)obj.Properties["SerialNumber"].Value ?? string.Empty;
}
using var sha1 = SHA1.Create();
ret = string.Join("", sha1.ComputeHash(Encoding.UTF8.GetBytes(concatStr)).Select(b => b.ToString("x2")));
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
return ret;
}
I reverse engineered the Unity Editor to find out what it actually queries in the WMI.
This is obviously the Windows Implementation.

https://docs.unity3d.com/ScriptReference/SystemInfo-deviceUniqueIdentifier.html
SystemInfo.deviceUniqueIdentifier
Leave feedback
public static string deviceUniqueIdentifier;
Description
A unique device identifier. It is guaranteed to be unique for every device (Read Only).
iOS: on pre-iOS7 devices it will return hash of MAC address. On iOS7 devices it will be UIDevice identifierForVendor or, if that fails for any reason, ASIdentifierManager advertisingIdentifier.
Android: SystemInfo.deviceUniqueIdentifier always returns the md5 of ANDROID_ID. (See https://developer.android.com/reference/android/provider/Settings.Secure.html#ANDROID_ID). Note that since Android 8.0 (API level 26) ANDROID_ID depends on the app signing key. That means "unsigned" builds (which are by default signed with a debug keystore) will have a different value than signed builds (which are signed with a key provided in the player settings). Also when allowing Google Play to sign your app, this value will be different when testing locally built app which is signed with the upload key and app downloaded from the Google Play which will be signed with the "final" key.
Windows Store Apps: uses AdvertisingManager::AdvertisingId for returning unique device identifier, if option in 'PC Settings -> Privacy -> Let apps use my advertising ID for experiences across apps (turning this off will reset your ID)' is disabled, Unity will fallback to HardwareIdentification::GetPackageSpecificToken().Id.
Windows Standalone: returns a hash from the concatenation of strings taken from Computer System Hardware Classes (https://msdn.microsoft.com/en-us/library/windows/desktop/aa389273(v=vs.85).aspx):
Win32_BaseBoard::SerialNumber
Win32_BIOS::SerialNumber
Win32_Processor::UniqueId
Win32_DiskDrive::SerialNumber
Win32_OperatingSystem::SerialNumber

How to find usb port using in C# [duplicate]

How can I get a list of all the connected USB devices on a windows computer?

Add a reference to System.Management for your project, then try something like this:
using System;
using System.Collections.Generic;
using System.Management; // need to add System.Management to your project references.
class Program
{
static void Main(string[] args)
{
var usbDevices = GetUSBDevices();
foreach (var usbDevice in usbDevices)
{
Console.WriteLine(
$"Device ID: {usbDevice.DeviceID}, PNP Device ID: {usbDevice.PnpDeviceID}, Description: {usbDevice.Description}");
}
Console.Read();
}
static List<USBDeviceInfo> GetUSBDevices()
{
List<USBDeviceInfo> devices = new List<USBDeviceInfo>();
using var searcher = new ManagementObjectSearcher(
#"Select * From Win32_USBHub");
using ManagementObjectCollection collection = searcher.Get();
foreach (var device in collection)
{
devices.Add(new USBDeviceInfo(
(string)device.GetPropertyValue("DeviceID"),
(string)device.GetPropertyValue("PNPDeviceID"),
(string)device.GetPropertyValue("Description")
));
}
return devices;
}
}
class USBDeviceInfo
{
public USBDeviceInfo(string deviceID, string pnpDeviceID, string description)
{
this.DeviceID = deviceID;
this.PnpDeviceID = pnpDeviceID;
this.Description = description;
}
public string DeviceID { get; private set; }
public string PnpDeviceID { get; private set; }
public string Description { get; private set; }
}

I know I'm replying to an old question, but I just went through this same exercise and found out a bit more information, that I think will contribute a lot to the discussion and help out anyone else who finds this question and sees where the existing answers fall short.
The accepted answer is close, and can be corrected using Nedko's comment to it. A more detailed understanding of the WMI Classes involved helps complete the picture.
Win32_USBHub returns only USB Hubs. That seems obvious in hindsight but the discussion above misses it. It does not include all possible USB devices, only those which can (in theory, at least) act as a hub for additional devices. It misses some devices that are not hubs (particularly parts of composite devices).
Win32_PnPEntity does include all the USB devices, and hundreds more non-USB devices. Russel Gantman's advice to use a WHERE clause search Win32_PnPEntity for a DeviceID beginning with "USB%" to filter the list is helpful but slightly incomplete; it misses bluetooth devices, some printers/print servers, and HID-compliant mice and keyboards. I have seen "USB\%", "USBSTOR\%", "USBPRINT\%", "BTH\%", "SWD\%", and "HID\%". Win32_PnPEntity is, however, a good "master" reference to look up information once you are in possession of the PNPDeviceID from other sources.
What I found was the best way to enumerate USB devices was to query Win32_USBControllerDevice. While it doesn't give detailed information for the devices, it does completely enumerate your USB devices and gives you an Antecedent/Dependent pair of PNPDeviceIDs for every USB Device (including Hubs, non-Hub devices, and HID-compliant devices) on your system. Each Dependent returned from the query will be a USB Device. The Antecedent will be the Controller it is assigned to, one of the USB Controllers returned by querying Win32_USBController.
As a bonus, it appears that under the hood, WMI walks the Device Tree when responding to the Win32_USBControllerDevice query, so the order in which these results are returned can help identify parent/child relationships. (This is not documented and is thus only a guess; use the SetupDi API's CM_Get_Parent (or Child + Sibling) for definitive results.) As an option to the SetupDi API, it appears that for all the devices listed under Win32_USBHub they can be looked up in the registry (at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\ + PNPDeviceID) and will have a parameter ParentIdPrefix which will be the prefix of the last field in the PNPDeviceID of its children, so this could also be used in a wildcard match to filter the Win32_PnPEntity query.
In my application, I did the following:
(Optional) Queried Win32_PnPEntity and stored the results in a key-value map (with PNPDeviceID as the key) for later retrieval. This is optional if you want to do individual queries later.
Queried Win32_USBControllerDevice for a definitive list of USB devices on my system (all the Dependents) and extracted the PNPDeviceIDs of these. I went further, based on order following the device tree, to assign devices to the root hub (the first device returned, rather than the controller) and built a tree based on the parentIdPrefix. The order the query returns, which matches device tree enumeration via SetupDi, is each root hub (for whom the Antecedent identifies the controller), followed by an iteration of devices under it, e.g., on my system:
Root hub of first controller
Root hub of second controller
First hub under root hub of second controller (has parentIdPrefix)
First composite device under first hub under root hub of second controller (PNPDeviceID matches above hub's ParentIdPrefix; has its own ParentIdPrefix)
HID Device part of the composite device (PNPDeviceID matches above composite device's ParentIDPrefix)
Second device under first hub under root hub of second controller
HID Device part of the composite device
Second hub under root hub of second controller
First device under second hub under root hub of second controller
Third hub under root hub of second controller
etc.
Queried Win32_USBController. This gave me the detailed information of the PNPDeviceIDs of my controllers which are at the top of the device tree (which were the Antecedents of the previous query). Using the tree derived in the previous step, recursively iterated over its children (the root hubs) and their children (the other hubs) and their children (non-hub devices and composite devices) and their children, etc.
Retrieved details for each device in my tree by referencing the map stored in the first step. (Optionally, one could skip the first step, and query Win32_PnPEntity individually using the PNPDeviceId to get the information at this step; probably a cpu vs. memory tradeoff determining which order is better.)
In summary, Win32USBControllerDevice Dependents are a complete list of USB Devices on a system (other than the Controllers themselves, which are the Antecedents in that same query), and by cross-referencing these PNPDeviceId pairs with information from the registry and from the other queries mentioned, a detailed picture can be constructed.

To see the devices I was interested in, I had replace Win32_USBHub by Win32_PnPEntity in Adel Hazzah's code, based on this post. This works for me:
namespace ConsoleApplication1
{
using System;
using System.Collections.Generic;
using System.Management; // need to add System.Management to your project references.
class Program
{
static void Main(string[] args)
{
var usbDevices = GetUSBDevices();
foreach (var usbDevice in usbDevices)
{
Console.WriteLine("Device ID: {0}, PNP Device ID: {1}, Description: {2}",
usbDevice.DeviceID, usbDevice.PnpDeviceID, usbDevice.Description);
}
Console.Read();
}
static List<USBDeviceInfo> GetUSBDevices()
{
List<USBDeviceInfo> devices = new List<USBDeviceInfo>();
ManagementObjectCollection collection;
using (var searcher = new ManagementObjectSearcher(#"Select * From Win32_PnPEntity"))
collection = searcher.Get();
foreach (var device in collection)
{
devices.Add(new USBDeviceInfo(
(string)device.GetPropertyValue("DeviceID"),
(string)device.GetPropertyValue("PNPDeviceID"),
(string)device.GetPropertyValue("Description")
));
}
collection.Dispose();
return devices;
}
}
class USBDeviceInfo
{
public USBDeviceInfo(string deviceID, string pnpDeviceID, string description)
{
this.DeviceID = deviceID;
this.PnpDeviceID = pnpDeviceID;
this.Description = description;
}
public string DeviceID { get; private set; }
public string PnpDeviceID { get; private set; }
public string Description { get; private set; }
}
}

Adel Hazzah's answer gives working code, Daniel Widdis's and Nedko's comments mention that you need to query Win32_USBControllerDevice and use its Dependent property, and Daniel's answer gives a lot of detail without code.
Here's a synthesis of the above discussion to provide working code that lists the directly accessible PNP device properties of all connected USB devices:
using System;
using System.Collections.Generic;
using System.Management; // reference required
namespace cSharpUtilities
{
class UsbBrowser
{
public static void PrintUsbDevices()
{
IList<ManagementBaseObject> usbDevices = GetUsbDevices();
foreach (ManagementBaseObject usbDevice in usbDevices)
{
Console.WriteLine("----- DEVICE -----");
foreach (var property in usbDevice.Properties)
{
Console.WriteLine(string.Format("{0}: {1}", property.Name, property.Value));
}
Console.WriteLine("------------------");
}
}
public static IList<ManagementBaseObject> GetUsbDevices()
{
IList<string> usbDeviceAddresses = LookUpUsbDeviceAddresses();
List<ManagementBaseObject> usbDevices = new List<ManagementBaseObject>();
foreach (string usbDeviceAddress in usbDeviceAddresses)
{
// query MI for the PNP device info
// address must be escaped to be used in the query; luckily, the form we extracted previously is already escaped
ManagementObjectCollection curMoc = QueryMi("Select * from Win32_PnPEntity where PNPDeviceID = " + usbDeviceAddress);
foreach (ManagementBaseObject device in curMoc)
{
usbDevices.Add(device);
}
}
return usbDevices;
}
public static IList<string> LookUpUsbDeviceAddresses()
{
// this query gets the addressing information for connected USB devices
ManagementObjectCollection usbDeviceAddressInfo = QueryMi(#"Select * from Win32_USBControllerDevice");
List<string> usbDeviceAddresses = new List<string>();
foreach(var device in usbDeviceAddressInfo)
{
string curPnpAddress = (string)device.GetPropertyValue("Dependent");
// split out the address portion of the data; note that this includes escaped backslashes and quotes
curPnpAddress = curPnpAddress.Split(new String[] { "DeviceID=" }, 2, StringSplitOptions.None)[1];
usbDeviceAddresses.Add(curPnpAddress);
}
return usbDeviceAddresses;
}
// run a query against Windows Management Infrastructure (MI) and return the resulting collection
public static ManagementObjectCollection QueryMi(string query)
{
ManagementObjectSearcher managementObjectSearcher = new ManagementObjectSearcher(query);
ManagementObjectCollection result = managementObjectSearcher.Get();
managementObjectSearcher.Dispose();
return result;
}
}
}
You'll need to add exception handling if you want it. Consult Daniel's answer if you want to figure out the device tree and such.

If you change the ManagementObjectSearcher to the following:
ManagementObjectSearcher searcher =
new ManagementObjectSearcher("root\\CIMV2",
#"SELECT * FROM Win32_PnPEntity where DeviceID Like ""USB%""");
So the "GetUSBDevices() looks like this"
static List<USBDeviceInfo> GetUSBDevices()
{
List<USBDeviceInfo> devices = new List<USBDeviceInfo>();
ManagementObjectCollection collection;
using (var searcher = new ManagementObjectSearcher(#"SELECT * FROM Win32_PnPEntity where DeviceID Like ""USB%"""))
collection = searcher.Get();
foreach (var device in collection)
{
devices.Add(new USBDeviceInfo(
(string)device.GetPropertyValue("DeviceID"),
(string)device.GetPropertyValue("PNPDeviceID"),
(string)device.GetPropertyValue("Description")
));
}
collection.Dispose();
return devices;
}
}
Your results will be limited to USB devices (as opposed to all types on your system)

This is a much simpler example for people only looking for removable usb drives.
using System.IO;
foreach (DriveInfo drive in DriveInfo.GetDrives())
{
if (drive.DriveType == DriveType.Removable)
{
Console.WriteLine(string.Format("({0}) {1}", drive.Name.Replace("\\",""), drive.VolumeLabel));
}
}

You may find this thread useful. And here's a google code project exemplifying this (it P/Invokes into setupapi.dll).

lstResult.Clear();
foreach (ManagementObject drive in new ManagementObjectSearcher("select * from Win32_DiskDrive where InterfaceType='USB'").Get())
{
foreach (ManagementObject partition in new ManagementObjectSearcher("ASSOCIATORS OF {Win32_DiskDrive.DeviceID='" + drive["DeviceID"] + "'} WHERE AssocClass = Win32_DiskDriveToDiskPartition").Get())
{
foreach (ManagementObject disk in new ManagementObjectSearcher("ASSOCIATORS OF {Win32_DiskPartition.DeviceID='" + partition["DeviceID"] + "'} WHERE AssocClass = Win32_LogicalDiskToPartition").Get())
{
foreach (var item in disk.Properties)
{
object value = disk.GetPropertyValue(item.Name);
}
string valor = disk["Name"].ToString();
lstResult.Add(valor);
}
}
}
}

Querying if a Windows Service is disabled (without using the Registry)?

Is there a .NET (C#) method or API call that I can use to query if a Windows Service is disabled? The relevant MSDN article is here.
I want to avoid querying the registry directly. Below is some of the code that I am using right now (and it works). However I am looking for something more elegant and less invasive.
const String basepathStr = #"System\CurrentControlSet\services\";
String subKeyStr = basepathStr + servicenameStr;
using (RegistryKey key = Registry.LocalMachine.OpenSubKey(subKeyStr))
{
return (int) key.GetValue("Start");
}
I did find a simliar question but I was hoping for a better answer since the answers are presumably outdated (3 years have passed).

This the most relevant section of the code I decided to use...thanks for the help all!
StartupState state = StartupState.Unknown;
try
{
PermissionSet fullTrust = new PermissionSet(System.Security.Permissions.PermissionState.Unrestricted);
fullTrust.Demand();
string wmiQuery = #"SELECT * FROM Win32_Service WHERE Name='" + servicenameStr + #"'";
ManagementObjectSearcher searcher = new ManagementObjectSearcher(wmiQuery);
ManagementObjectCollection results = searcher.Get();
foreach (ManagementObject service in results)
{
if (service["StartMode"].ToString() == "Disabled")
state = StartupState.Disabled;
else
state = StartupState.Enabled;
}
return state;
}
catch (SecurityException se)
{
return StartupState.Refused;
}
catch (Exception e)
{
return StartupState.Error;
}

Use the ServiceController class to get information about services.
EDIT
Seems one of the things you can't do with the ServiceController is get the startup type. Googling showed the following blog post that has code that uses P/Invoke to get the service startup type: http://peterkellyonline.blogspot.de/2011/04/configuring-windows-service.html

Add a ref to System.Management and the following code will get you the StartMode
string wmiQuery = "SELECT * FROM Win32_Service WHERE Name='YourServiceName'";
var searcher = new ManagementObjectSearcher(wmiQuery);
var results = searcher.Get();
foreach (ManagementObject service in results)
{
Console.WriteLine(service["StartMode"]);
}

ServiceController class doesn't provide this information. You should use WMI. See here for detailed solution

WMI can be another way for querying the status of the windows services

You can use:
using System.ServiceProcess;
And then link the service you want to view the satus by:
// Link by service name
ServiceController TheServiceName = new ServiceController();
TheServiceName.ServiceName = "Spooler";
// Link by display name
ServiceController TheDisplayName = new ServiceController();
TheDisplayName.ServiceName = "Print Spooler";
To check for example the isRunning Status :
if (TheServiceName.Status == ServiceControllerStatus.Running)
MessageBox.Show("The service is running.");

Get List of connected USB Devices

How can I get a list of all the connected USB devices on a windows computer?

Add a reference to System.Management for your project, then try something like this:
using System;
using System.Collections.Generic;
using System.Management; // need to add System.Management to your project references.
class Program
{
static void Main(string[] args)
{
var usbDevices = GetUSBDevices();
foreach (var usbDevice in usbDevices)
{
Console.WriteLine(
$"Device ID: {usbDevice.DeviceID}, PNP Device ID: {usbDevice.PnpDeviceID}, Description: {usbDevice.Description}");
}
Console.Read();
}
static List<USBDeviceInfo> GetUSBDevices()
{
List<USBDeviceInfo> devices = new List<USBDeviceInfo>();
using var searcher = new ManagementObjectSearcher(
#"Select * From Win32_USBHub");
using ManagementObjectCollection collection = searcher.Get();
foreach (var device in collection)
{
devices.Add(new USBDeviceInfo(
(string)device.GetPropertyValue("DeviceID"),
(string)device.GetPropertyValue("PNPDeviceID"),
(string)device.GetPropertyValue("Description")
));
}
return devices;
}
}
class USBDeviceInfo
{
public USBDeviceInfo(string deviceID, string pnpDeviceID, string description)
{
this.DeviceID = deviceID;
this.PnpDeviceID = pnpDeviceID;
this.Description = description;
}
public string DeviceID { get; private set; }
public string PnpDeviceID { get; private set; }
public string Description { get; private set; }
}

I know I'm replying to an old question, but I just went through this same exercise and found out a bit more information, that I think will contribute a lot to the discussion and help out anyone else who finds this question and sees where the existing answers fall short.
The accepted answer is close, and can be corrected using Nedko's comment to it. A more detailed understanding of the WMI Classes involved helps complete the picture.
Win32_USBHub returns only USB Hubs. That seems obvious in hindsight but the discussion above misses it. It does not include all possible USB devices, only those which can (in theory, at least) act as a hub for additional devices. It misses some devices that are not hubs (particularly parts of composite devices).
Win32_PnPEntity does include all the USB devices, and hundreds more non-USB devices. Russel Gantman's advice to use a WHERE clause search Win32_PnPEntity for a DeviceID beginning with "USB%" to filter the list is helpful but slightly incomplete; it misses bluetooth devices, some printers/print servers, and HID-compliant mice and keyboards. I have seen "USB\%", "USBSTOR\%", "USBPRINT\%", "BTH\%", "SWD\%", and "HID\%". Win32_PnPEntity is, however, a good "master" reference to look up information once you are in possession of the PNPDeviceID from other sources.
What I found was the best way to enumerate USB devices was to query Win32_USBControllerDevice. While it doesn't give detailed information for the devices, it does completely enumerate your USB devices and gives you an Antecedent/Dependent pair of PNPDeviceIDs for every USB Device (including Hubs, non-Hub devices, and HID-compliant devices) on your system. Each Dependent returned from the query will be a USB Device. The Antecedent will be the Controller it is assigned to, one of the USB Controllers returned by querying Win32_USBController.
As a bonus, it appears that under the hood, WMI walks the Device Tree when responding to the Win32_USBControllerDevice query, so the order in which these results are returned can help identify parent/child relationships. (This is not documented and is thus only a guess; use the SetupDi API's CM_Get_Parent (or Child + Sibling) for definitive results.) As an option to the SetupDi API, it appears that for all the devices listed under Win32_USBHub they can be looked up in the registry (at HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\ + PNPDeviceID) and will have a parameter ParentIdPrefix which will be the prefix of the last field in the PNPDeviceID of its children, so this could also be used in a wildcard match to filter the Win32_PnPEntity query.
In my application, I did the following:
(Optional) Queried Win32_PnPEntity and stored the results in a key-value map (with PNPDeviceID as the key) for later retrieval. This is optional if you want to do individual queries later.
Queried Win32_USBControllerDevice for a definitive list of USB devices on my system (all the Dependents) and extracted the PNPDeviceIDs of these. I went further, based on order following the device tree, to assign devices to the root hub (the first device returned, rather than the controller) and built a tree based on the parentIdPrefix. The order the query returns, which matches device tree enumeration via SetupDi, is each root hub (for whom the Antecedent identifies the controller), followed by an iteration of devices under it, e.g., on my system:
Root hub of first controller
Root hub of second controller
First hub under root hub of second controller (has parentIdPrefix)
First composite device under first hub under root hub of second controller (PNPDeviceID matches above hub's ParentIdPrefix; has its own ParentIdPrefix)
HID Device part of the composite device (PNPDeviceID matches above composite device's ParentIDPrefix)
Second device under first hub under root hub of second controller
HID Device part of the composite device
Second hub under root hub of second controller
First device under second hub under root hub of second controller
Third hub under root hub of second controller
etc.
Queried Win32_USBController. This gave me the detailed information of the PNPDeviceIDs of my controllers which are at the top of the device tree (which were the Antecedents of the previous query). Using the tree derived in the previous step, recursively iterated over its children (the root hubs) and their children (the other hubs) and their children (non-hub devices and composite devices) and their children, etc.
Retrieved details for each device in my tree by referencing the map stored in the first step. (Optionally, one could skip the first step, and query Win32_PnPEntity individually using the PNPDeviceId to get the information at this step; probably a cpu vs. memory tradeoff determining which order is better.)
In summary, Win32USBControllerDevice Dependents are a complete list of USB Devices on a system (other than the Controllers themselves, which are the Antecedents in that same query), and by cross-referencing these PNPDeviceId pairs with information from the registry and from the other queries mentioned, a detailed picture can be constructed.

To see the devices I was interested in, I had replace Win32_USBHub by Win32_PnPEntity in Adel Hazzah's code, based on this post. This works for me:
namespace ConsoleApplication1
{
using System;
using System.Collections.Generic;
using System.Management; // need to add System.Management to your project references.
class Program
{
static void Main(string[] args)
{
var usbDevices = GetUSBDevices();
foreach (var usbDevice in usbDevices)
{
Console.WriteLine("Device ID: {0}, PNP Device ID: {1}, Description: {2}",
usbDevice.DeviceID, usbDevice.PnpDeviceID, usbDevice.Description);
}
Console.Read();
}
static List<USBDeviceInfo> GetUSBDevices()
{
List<USBDeviceInfo> devices = new List<USBDeviceInfo>();
ManagementObjectCollection collection;
using (var searcher = new ManagementObjectSearcher(#"Select * From Win32_PnPEntity"))
collection = searcher.Get();
foreach (var device in collection)
{
devices.Add(new USBDeviceInfo(
(string)device.GetPropertyValue("DeviceID"),
(string)device.GetPropertyValue("PNPDeviceID"),
(string)device.GetPropertyValue("Description")
));
}
collection.Dispose();
return devices;
}
}
class USBDeviceInfo
{
public USBDeviceInfo(string deviceID, string pnpDeviceID, string description)
{
this.DeviceID = deviceID;
this.PnpDeviceID = pnpDeviceID;
this.Description = description;
}
public string DeviceID { get; private set; }
public string PnpDeviceID { get; private set; }
public string Description { get; private set; }
}
}

Adel Hazzah's answer gives working code, Daniel Widdis's and Nedko's comments mention that you need to query Win32_USBControllerDevice and use its Dependent property, and Daniel's answer gives a lot of detail without code.
Here's a synthesis of the above discussion to provide working code that lists the directly accessible PNP device properties of all connected USB devices:
using System;
using System.Collections.Generic;
using System.Management; // reference required
namespace cSharpUtilities
{
class UsbBrowser
{
public static void PrintUsbDevices()
{
IList<ManagementBaseObject> usbDevices = GetUsbDevices();
foreach (ManagementBaseObject usbDevice in usbDevices)
{
Console.WriteLine("----- DEVICE -----");
foreach (var property in usbDevice.Properties)
{
Console.WriteLine(string.Format("{0}: {1}", property.Name, property.Value));
}
Console.WriteLine("------------------");
}
}
public static IList<ManagementBaseObject> GetUsbDevices()
{
IList<string> usbDeviceAddresses = LookUpUsbDeviceAddresses();
List<ManagementBaseObject> usbDevices = new List<ManagementBaseObject>();
foreach (string usbDeviceAddress in usbDeviceAddresses)
{
// query MI for the PNP device info
// address must be escaped to be used in the query; luckily, the form we extracted previously is already escaped
ManagementObjectCollection curMoc = QueryMi("Select * from Win32_PnPEntity where PNPDeviceID = " + usbDeviceAddress);
foreach (ManagementBaseObject device in curMoc)
{
usbDevices.Add(device);
}
}
return usbDevices;
}
public static IList<string> LookUpUsbDeviceAddresses()
{
// this query gets the addressing information for connected USB devices
ManagementObjectCollection usbDeviceAddressInfo = QueryMi(#"Select * from Win32_USBControllerDevice");
List<string> usbDeviceAddresses = new List<string>();
foreach(var device in usbDeviceAddressInfo)
{
string curPnpAddress = (string)device.GetPropertyValue("Dependent");
// split out the address portion of the data; note that this includes escaped backslashes and quotes
curPnpAddress = curPnpAddress.Split(new String[] { "DeviceID=" }, 2, StringSplitOptions.None)[1];
usbDeviceAddresses.Add(curPnpAddress);
}
return usbDeviceAddresses;
}
// run a query against Windows Management Infrastructure (MI) and return the resulting collection
public static ManagementObjectCollection QueryMi(string query)
{
ManagementObjectSearcher managementObjectSearcher = new ManagementObjectSearcher(query);
ManagementObjectCollection result = managementObjectSearcher.Get();
managementObjectSearcher.Dispose();
return result;
}
}
}
You'll need to add exception handling if you want it. Consult Daniel's answer if you want to figure out the device tree and such.

If you change the ManagementObjectSearcher to the following:
ManagementObjectSearcher searcher =
new ManagementObjectSearcher("root\\CIMV2",
#"SELECT * FROM Win32_PnPEntity where DeviceID Like ""USB%""");
So the "GetUSBDevices() looks like this"
static List<USBDeviceInfo> GetUSBDevices()
{
List<USBDeviceInfo> devices = new List<USBDeviceInfo>();
ManagementObjectCollection collection;
using (var searcher = new ManagementObjectSearcher(#"SELECT * FROM Win32_PnPEntity where DeviceID Like ""USB%"""))
collection = searcher.Get();
foreach (var device in collection)
{
devices.Add(new USBDeviceInfo(
(string)device.GetPropertyValue("DeviceID"),
(string)device.GetPropertyValue("PNPDeviceID"),
(string)device.GetPropertyValue("Description")
));
}
collection.Dispose();
return devices;
}
}
Your results will be limited to USB devices (as opposed to all types on your system)

This is a much simpler example for people only looking for removable usb drives.
using System.IO;
foreach (DriveInfo drive in DriveInfo.GetDrives())
{
if (drive.DriveType == DriveType.Removable)
{
Console.WriteLine(string.Format("({0}) {1}", drive.Name.Replace("\\",""), drive.VolumeLabel));
}
}

You may find this thread useful. And here's a google code project exemplifying this (it P/Invokes into setupapi.dll).

lstResult.Clear();
foreach (ManagementObject drive in new ManagementObjectSearcher("select * from Win32_DiskDrive where InterfaceType='USB'").Get())
{
foreach (ManagementObject partition in new ManagementObjectSearcher("ASSOCIATORS OF {Win32_DiskDrive.DeviceID='" + drive["DeviceID"] + "'} WHERE AssocClass = Win32_DiskDriveToDiskPartition").Get())
{
foreach (ManagementObject disk in new ManagementObjectSearcher("ASSOCIATORS OF {Win32_DiskPartition.DeviceID='" + partition["DeviceID"] + "'} WHERE AssocClass = Win32_LogicalDiskToPartition").Get())
{
foreach (var item in disk.Properties)
{
object value = disk.GetPropertyValue(item.Name);
}
string valor = disk["Name"].ToString();
lstResult.Add(valor);
}
}
}
}