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c#managementeventwatcher

How do I get newly inserted USB drive letter in c#?


I wrote a c# program to find newly inserted USB drive and its drive letter. Now when I run this program I got the insertion event and couldn't get the drive letter. Can anyone suggest me an idea to do this?

code

static void Main(string[] args)
{
    ManagementEventWatcher mwe_creation; //Object creation for 'ManagementEventWatcher' class is used to listen the temporary system event notofications based on specific query. 
    WqlEventQuery q_creation = new WqlEventQuery(); //Represents WMI(Windows Management Instrumentation) event query in WQL format for more information goto www.en.wikipedia.org/wiki/WQL
    q_creation.EventClassName = "__InstanceCreationEvent";// Sets the eventclass to the query
    q_creation.WithinInterval = new TimeSpan(0, 0, 2);    // Setting up the time interval for the event check(here, it is 2 Seconds)
    q_creation.Condition = @"TargetInstance ISA 'Win32_DiskDriveToDiskPartition'"; //Sets which kind of event  to be notified
    mwe_creation = new ManagementEventWatcher(q_creation); //Initializing new instance
    mwe_creation.EventArrived += new EventArrivedEventHandler(USBEventArrived_Creation);//Calling up 'USBEventArrived_Creation' method when the usb storage plug-in event occured
    mwe_creation.Start(); // Starting to listen to the system events based on the given query
    while (true) ;

}
static void USBEventArrived_Creation(object sender, EventArrivedEventArgs e){

    Console.WriteLine("USB PLUGGED IN!");
    ManagementBaseObject instance = (ManagementBaseObject)e.NewEvent["TargetInstance"];
    foreach (var property in instance.Properties)
    {

        if (property.Name == "Name")
            Console.WriteLine(property.Name + " = " + property.Value);
    }

}

Solution

  • You may be working too hard to recreate a pre-existing soultion. Here is a Public-Licensed project made by Stephen Mcohn that provides exactly the interface you need and appears to be well documented:

    http://www.codeproject.com/Articles/63878/Enumerate-and-Auto-Detect-USB-Drives

    Here is how he filtered for just USB drives

    new ManagementObjectSearcher(
            "select DeviceID, Model from Win32_DiskDrive " +
             "where InterfaceType='USB'").Get())
    

    Here is how the specific drive letter was recovered

    Getting the specific drive letter was accomplished using Associators to get the Win32_LogicalDisk which can then give the device ID (e.g. drive letter).

    Microsoft Provided a VB code example that you can port if you don't want to just import Stephen's whole module:

    ComputerName = "."
    Set wmiServices  = GetObject ( _
        "winmgmts:{impersonationLevel=Impersonate}!//" & ComputerName)
    ' Get physical disk drive
    Set wmiDiskDrives =  wmiServices.ExecQuery ( "SELECT Caption, DeviceID FROM Win32_DiskDrive")
    
    For Each wmiDiskDrive In wmiDiskDrives
        WScript.Echo "Disk drive Caption: " & wmiDiskDrive.Caption & VbNewLine & "DeviceID: " & " (" & wmiDiskDrive.DeviceID & ")"
    
        'Use the disk drive device id to
        ' find associated partition
        query = "ASSOCIATORS OF {Win32_DiskDrive.DeviceID='" _
            & wmiDiskDrive.DeviceID & "'} WHERE AssocClass = Win32_DiskDriveToDiskPartition"    
        Set wmiDiskPartitions = wmiServices.ExecQuery(query)
    
        For Each wmiDiskPartition In wmiDiskPartitions
            'Use partition device id to find logical disk
            Set wmiLogicalDisks = wmiServices.ExecQuery _
                ("ASSOCIATORS OF {Win32_DiskPartition.DeviceID='" _
                 & wmiDiskPartition.DeviceID & "'} WHERE AssocClass = Win32_LogicalDiskToPartition") 
    
            For Each wmiLogicalDisk In wmiLogicalDisks
                WScript.Echo "Drive letter associated" _
                    & " with disk drive = " _ 
                    & wmiDiskDrive.Caption _
                    & wmiDiskDrive.DeviceID _
                    & VbNewLine & " Partition = " _
                    & wmiDiskPartition.DeviceID _
                    & VbNewLine & " is " _
                    & wmiLogicalDisk.DeviceID
            Next      
        Next
    Next