How to get the drive letter of USB device using WMI

Question

I need to track the USB insertion and removal events from the C# application so I came up with the following ideas based on the other questions on SO.

I can\'t use this

Answer 1

You get an exception because your deviceID contains characters that need to be escaped (backslashes). With simple replace you shouldn't get the exception.

string query = string.Format("SELECT * FROM Win32_LogicalDisk WHERE DeviceID='{0}'", deviceID.Replace(@"\", @"\\"));

However, getting USB drive letter from WMI is a little more complicated. You need to go through a few classes, as stated in a link that @MSalters posted in his comment:

Win32_DiskDrive-> Win32_DiskDriveToDiskPartition -> Win32_DiskPartition -> Win32_LogicalDiskToPartition -> Win32_LogicalDisk.

A little modified version of code found here worked for me:

foreach (ManagementObject device in new ManagementObjectSearcher(@"SELECT * FROM Win32_DiskDrive WHERE InterfaceType LIKE 'USB%'").Get())
{
    Console.WriteLine((string)device.GetPropertyValue("DeviceID"));
    Console.WriteLine((string)device.GetPropertyValue("PNPDeviceID"));                

    foreach (ManagementObject partition in new ManagementObjectSearcher(
        "ASSOCIATORS OF {Win32_DiskDrive.DeviceID='" + device.Properties["DeviceID"].Value
        + "'} WHERE AssocClass = Win32_DiskDriveToDiskPartition").Get())
    {
        foreach (ManagementObject disk in new ManagementObjectSearcher(
                    "ASSOCIATORS OF {Win32_DiskPartition.DeviceID='"
                        + partition["DeviceID"]
                        + "'} WHERE AssocClass = Win32_LogicalDiskToPartition").Get())
        {
            Console.WriteLine("Drive letter " + disk["Name"]);
        }
    }
}

Answer 2

This is a refactored version of michalk's answer for C# 8.

I used it in combination with the answers for this, Detecting USB drive insertion and removal using windows service and c#, related question

        static IEnumerable<(string deviceId, string pnpDeviceId, string driveLetter)> SelectDeviceInformation()
        {
            foreach (ManagementObject device in SelectDevices())
            {
                var deviceId = (string)device.GetPropertyValue("DeviceID");
                var pnpDeviceId = (string)device.GetPropertyValue("PNPDeviceID");
                var driveLetter = (string)SelectPartitions(device).SelectMany(SelectDisks).Select(disk => disk["Name"]).Single();

                yield return (deviceId, pnpDeviceId, driveLetter);
            }

            static IEnumerable<ManagementObject> SelectDevices() => new ManagementObjectSearcher(
                    @"SELECT * FROM Win32_DiskDrive WHERE InterfaceType LIKE 'USB%'").Get()
                .Cast<ManagementObject>();

            static IEnumerable<ManagementObject> SelectPartitions(ManagementObject device) => new ManagementObjectSearcher(
                    "ASSOCIATORS OF {Win32_DiskDrive.DeviceID=" +
                    "'" + device.Properties["DeviceID"].Value + "'} " +
                    "WHERE AssocClass = Win32_DiskDriveToDiskPartition").Get()
                .Cast<ManagementObject>();

            static IEnumerable<ManagementObject> SelectDisks(ManagementObject partition) => new ManagementObjectSearcher(
                    "ASSOCIATORS OF {Win32_DiskPartition.DeviceID=" +
                    "'" + partition["DeviceID"] + "'" +
                    "} WHERE AssocClass = Win32_LogicalDiskToPartition").Get()
                .Cast<ManagementObject>();
        }