USB Storage device

[basti42]

hello!
how would i know if the USB Storage device is inserted
and determine the drive letter?

========
VS 2005

[Plater]

It is possible to do this with the windows message pump.
It's not easy. (I think there might be a WMI event for it, but I don't know of it)

Here's a bit of the code I use for it:

(put this in your form code)

[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name = "FullTrust")]
        protected override void WndProc(ref Message m)
        {
            if (m.Msg == (int)WM_Message.WM_DEVICECHANGE)
            {
                handleDeviceChange(m);
            }
            else
            {
                base.WndProc(ref m);
            }
        }
 
 
        private void handleDeviceChange(Message m)
        {
            DateTime now = DateTime.Now; 
            string msg = now.ToString()+" "+  "DeviceChanged: ";
            switch ((DBT_DeviceTypes)m.WParam)
            {
                case DBT_DeviceTypes.DBT_DEVICEARRIVAL:
                    msg += "   DEVICE ARRIVAL \r\n";
                    break;
                case DBT_DeviceTypes.DBT_DEVICEREMOVECOMPLETE:
                    msg += "   DEVICE REMOVE COMPLETE \r\n";
                    break;
                case DBT_DeviceTypes.DBT_DEVNODES_CHANGED:
                    msg += "   DEVICE NODES CHANGED \r\n";
                    break;
                default:
                    msg += "0x" + m.WParam.ToString("X4") + " \r\n";  
                    break;
            }
            if ((int)m.LParam != 0)
            {
                _DEV_BROADCAST_HANDLE dbh = (_DEV_BROADCAST_HANDLE)m.GetLParam(typeof(_DEV_BROADCAST_HANDLE));
                _DEV_BROADCAST_VOLUME dbv = (_DEV_BROADCAST_VOLUME)m.GetLParam(typeof(_DEV_BROADCAST_VOLUME));
                _DEV_BROADCAST_HDR db = (_DEV_BROADCAST_HDR)m.GetLParam(typeof(_DEV_BROADCAST_HDR));
 
                string drive = "   Drive: " + Messages.FirstDriveFromMask((UInt32)dbv.dbcv_unitmask) + ": \r\n";
                string flags = "   Flags: 0x" + dbv.dbcv_flags.ToString("X4")+" \r\n";
 
                string devicetype = "   Device Type: 0x" + dbh.dbch_devicetype.ToString("X4")+"\r\n";
                string packagesize = "   Size: 0x" + dbh.dbch_size.ToString("X4") + "\r\n";
                string eventid = "   EventGUID: 0x"+dbh.dbch_eventguid.ToString("X4")+"\r\n";
                string data = "   Data: 0x"+dbh.dbch_data.ToString("X2") + "\r\n";
 
                msg += drive;
                msg += flags;
                msg += devicetype;
                msg += packagesize;
                msg += eventid;
                msg += data;
 
                //tb1.AppendText(m.ToString() + "\r\n");
 
            }
            //do something with msg if you want
        }
 

You will need to get your hands on the ENUMs I used as well as what goes in those structs (they are all defined at msdn)

[TRScheel]

If you arent worried about performance, this will be helpful:

private static bool Continue = true;
 
[STAThread]
static void Main(string[] args)
{
    Thread thread = new Thread(DriveChecker);
    thread.Start();
    while (Continue)
    {
        if (Console.ReadLine() == "end")
            Continue = false;
    }
}
 
static void DriveChecker()
{
    List<string> currentDrives = new List<string>();
    while (Continue)
    {
 
        List<string> updatedDrives = new List<string>();
        for (int i = 100; i < 123; i++)
        {
            DirectoryInfo di = new DirectoryInfo(string.Format("{0}:\\", System.Text.ASCIIEncoding.ASCII.GetString(new byte[] { (byte)i })));
            if (di.Exists)
                updatedDrives.Add(System.Text.ASCIIEncoding.ASCII.GetString(new byte[] { (byte)i }));
        }
 
        updatedDrives.ForEach(delegate(string Drive) { if (!currentDrives.Contains(Drive)) { Console.WriteLine("Found New Drive: {0}", Drive); } });
        currentDrives.ForEach(delegate(string Drive) { if (!updatedDrives.Contains(Drive)) { Console.WriteLine("Lost Drive: {0}", Drive); } });
 
        currentDrives = updatedDrives;
 
        Thread.Sleep(100);   
    }
}
 

Increase the sleep time to increase performance. Type end to stop the console program.

EDIT:

100 - 123 are letters D - Z. We dont check A, B, or C.

[Plater]

Hehe, that is much more simple then mine.
Although mine will tell you if a CD/Disk has been inserted too.

[TRScheel]

Hehe, that is much more simple then mine.
Although mine will tell you if a CD/Disk has been inserted too.

Actually, it will catch the CD rom insertion... it just cant tell the difference between a CD and a USB stick.

[basti42]

tnx plater but there's an error

1. WM_Message
error: The name 'WM_Message' does not exist in the current context

2.
_DEV_BROADCAST_HANDLE dbh = (_DEV_BROADCAST_HANDLE)m.GetLParam(typeof(_DEV_BRO ADCAST_HANDLE));
_DEV_BROADCAST_VOLUME dbv = (_DEV_BROADCAST_VOLUME)m.GetLParam(typeof(_DEV_BRO ADCAST_VOLUME));
_DEV_BROADCAST_HDR db = (_DEV_BROADCAST_HDR)m.GetLParam(typeof(_DEV_BROADC AST_HDR));
error: Invalid expression term ')'

pls. help.

[basti42]

hello there! disregard my previous reply

i think i found what im lookin for, my next step now is how could i search all files including subfolders in the USB storage since it is obvious that i already know the drive letter?

ex: e:\*.* and e:\foldername1\foldername2

tnx in advance

[Plater]

Yeah, I didn't give you all the enums and structures because they're a few pages long, but they're easy to find online.

tnx plater but there's an error

1. WM_Message
error: The name 'WM_Message' does not exist in the current context

As for directory searching, look at the System.IO.Directory and System.IO.DirectoryInfo objects (they have a getfiles() and similar usefull functions)

[basti42]

i found this on microsoft's website

void DirSearch(string sDir)
{
try
{
foreach (string d in Directory.GetDirectories(sDir))
{
foreach (string f in Directory.GetFiles(d, txtFile.Text))
{
lstFilesFound.Items.Add(f);
}
DirSearch(d);
}
}
catch (System.Exception excpt)
{
Console.WriteLine(excpt.Message);
}
}

tnx plater!