/// <summary>
/// Populate the missing properties of the given disk before sending to listeners
/// </summary>
/// <param name="disk"></param>
private void GetDiskInformation(UsbDisk disk)
{
ManagementObject partition = new ManagementObjectSearcher(String.Format(
"associators of {{Win32_LogicalDisk.DeviceID='{0}'}} where AssocClass = Win32_LogicalDiskToPartition",
disk.Name)).First();
if (partition != null)
{
ManagementObject drive = new ManagementObjectSearcher(String.Format(
"associators of {{Win32_DiskPartition.DeviceID='{0}'}} where resultClass = Win32_DiskDrive",
partition["DeviceID"])).First();
if (drive != null)
{
disk.Model = drive["Model"].ToString();
}
ManagementObject volume = new ManagementObjectSearcher(String.Format(
"select FreeSpace, Size, VolumeName from Win32_LogicalDisk where Name='{0}'",
disk.Name)).First();
if (volume != null)
{
disk.Volume = volume["VolumeName"].ToString();
disk.FreeSpace = (ulong)volume["FreeSpace"];
disk.Size = (ulong)volume["Size"];
}
}
}
private void SignalDeviceChange(UsbStateChange state, DEV_BROADCAST_VOLUME volume)
{
string name = ToUnitName(volume.dbcv_unitmask);
if (StateChanged != null)
{
UsbDisk disk = new UsbDisk(name);
StateChanged(new UsbStateChangedEventArgs(state, disk));
}
}
//========================================================================================
// Methods
//========================================================================================
/// <summary>
/// Gets a collection of all available USB disk drives currently mounted.
/// </summary>
/// <returns>
/// A UsbDiskCollection containing the USB disk drives.
/// </returns>
public UsbDiskCollection GetAvailableDisks()
{
UsbDiskCollection disks = new UsbDiskCollection();
// browse all USB WMI physical disks
foreach (ManagementObject drive in
new ManagementObjectSearcher(
"select DeviceID, Model from Win32_DiskDrive where InterfaceType='USB'").Get())
{
// associate physical disks with partitions
ManagementObject partition = new ManagementObjectSearcher(String.Format(
"associators of {{Win32_DiskDrive.DeviceID='{0}'}} where AssocClass = Win32_DiskDriveToDiskPartition",
drive["DeviceID"])).First();
if (partition != null)
{
// associate partitions with logical disks (drive letter volumes)
ManagementObject logical = new ManagementObjectSearcher(String.Format(
"associators of {{Win32_DiskPartition.DeviceID='{0}'}} where AssocClass = Win32_LogicalDiskToPartition",
partition["DeviceID"])).First();
if (logical != null)
{
// finally find the logical disk entry to determine the volume name
ManagementObject volume = new ManagementObjectSearcher(String.Format(
"select FreeSpace, Size, VolumeName from Win32_LogicalDisk where Name='{0}'",
logical["Name"])).First();
UsbDisk disk = new UsbDisk(logical["Name"].ToString());
disk.Model = drive["Model"].ToString();
disk.Volume = volume["VolumeName"].ToString();
disk.FreeSpace = (ulong)volume["FreeSpace"];
disk.Size = (ulong)volume["Size"];
disks.Add(disk);
}
}
}
return(disks);
}
/// <summary>
/// Internally handle state changes and notify listeners.
/// </summary>
/// <param name="e"></param>
private void DoStateChanged(UsbStateChangedEventArgs e)
{
if (handler != null)
{
UsbDisk disk = e.Disk;
// we can only interrogate drives that are added...
// cannot see something that is no longer there!
if ((e.State == UsbStateChange.Added) && (e.Disk.Name[0] != '?'))
{
// the following Begin/End invokes looks strange but are required
// to resolve a "DisconnectedContext was detected" exception which
// occurs when the current thread terminates before the WMI queries
// can complete. I'm not exactly sure why that would happen...
GetDiskInformationDelegate gdi = new GetDiskInformationDelegate(GetDiskInformation);
IAsyncResult result = gdi.BeginInvoke(e.Disk, null, null);
gdi.EndInvoke(result);
}
handler(e);
}
}
/// <summary>
/// Initialize a new instance with the specified state and disk.
/// </summary>
/// <param name="state">The state change code.</param>
/// <param name="disk">The USB disk description.</param>
public UsbStateChangedEventArgs(UsbStateChange state, UsbDisk disk)
{
this.State = state;
this.Disk = disk;
}
