Question

I am writing a directory selector control for WPF, and I would like to add/remove a drive from the directory tree when it gets mounted or unmounted or when it becomes ready or not ready (e.g. the user inserts or removes a CD). I am looking for a system event similar to WM_DEVICECHANGE.

konstantin

Answer 1

I used WMI to implement something like this (like Richard stated in his answer)

using System.Management; 
using System;

...

private void SubscribeToCDInsertion()
{
    WqlEventQuery q;
    ManagementOperationObserver observer = new ManagementOperationObserver();

    // Bind to local machine
    ConnectionOptions opt = new ConnectionOptions();
    opt.EnablePrivileges = true; //sets required privilege
    ManagementScope scope = new ManagementScope("root\\CIMV2", opt);

    q = new WqlEventQuery();
    q.EventClassName = "__InstanceModificationEvent";
    q.WithinInterval = new TimeSpan(0, 0, 1);
    // DriveType - 5: CDROM
    q.Condition = @"TargetInstance ISA 'Win32_LogicalDisk' and TargetInstance.DriveType = 5";
    var w = new ManagementEventWatcher(scope, q);
    try
    {

       // register async. event handler
       w.EventArrived += new EventArrivedEventHandler(driveInsertEvent);
       w.Start();

    }
    catch (Exception e)
    {
        w.Stop();
    }

}

void driveInsertEvent(object sender, EventArrivedEventArgs e)
{
    // Get the Event object and display it
    PropertyData pd = e.NewEvent.Properties["TargetInstance"];

    if (pd != null)
    {
        ManagementBaseObject mbo = pd.Value as ManagementBaseObject;
        // if CD removed VolumeName == null
        if (mbo.Properties["VolumeName"].Value != null)
        {
            //do something
        }
    }
}

EDIT: I didn’t invent the code myself, I think I got it from here