Question

如何找到连接到系统的移除设备并提供其名称？

Answer 1

我假设你的意思是可移动设备。

以下是一些可以修改以满足您需求的代码。

using System;
using System.Collections.Generic;
using System.Text;
using System.Management;

namespace DeviceMonitor.Event
{
 /// <summary>Media watcher delegate.</summary>
 /// <param name="sender"></param>
 /// <param name="driveStatus"></param>
 public delegate void MediaWatcherEventHandler( object sender, DeviceMonitor.Event.MediaEvent.DriveStatus driveStatus );
 /// <summary>Class to monitor devices.</summary>
 public class MediaEvent
 {
  #region Variables

  /*------------------------------------------------------------------------*/
  private string m_logicalDrive;
  private ManagementEventWatcher m_managementEventWatcher = null;
  /*------------------------------------------------------------------------*/
  #endregion

  #region Events
  /*------------------------------------------------------------------------*/
  public event MediaWatcherEventHandler MediaWatcher;
  /*------------------------------------------------------------------------*/
  #endregion


  #region Enums
  /*------------------------------------------------------------------------*/
  /// <summary>The drive types.</summary>
  public enum DriveType
  {
   Unknown = 0,
   NoRootDirectory = 1,
   RemoveableDisk  = 2,
   LocalDisk       = 3,
   NetworkDrive    = 4,
   CompactDisk     = 5,
   RamDisk         = 6
  }

  /// <summary>The drive status.</summary>
  public enum DriveStatus
  {
   Unknown  = -1,
   Ejected  = 0,
   Inserted = 1,
  }
  /*-----------------------------------------------------------------------*/
  #endregion


  #region Monitoring
  /*-----------------------------------------------------------------------*/
  /// <summary>Starts the monitoring of device.</summary>
  /// <param name="path"></param>
  /// <param name="mediaEvent"></param>
  public void Monitor( string path, MediaEvent mediaEvent ) {
   if( null == mediaEvent ) {
    throw new ArgumentException( "Media event cannot be null!" );
   }

   //In case same class was called make sure only one instance is running
   /////////////////////////////////////////////////////////////
   this.Exit();

   //Keep logica drive to check
   /////////////////////////////////////////////////////////////
   this.m_logicalDrive = this.GetLogicalDrive( path );

   WqlEventQuery wql;
   ManagementOperationObserver observer = new
       ManagementOperationObserver();

   //Bind to local machine
   /////////////////////////////////////////////////////////////
   ConnectionOptions opt = new ConnectionOptions();

   //Sets required privilege
   /////////////////////////////////////////////////////////////
   opt.EnablePrivileges = true;
   ManagementScope scope = new ManagementScope( "root\\CIMV2", opt );

   try {
    wql = new WqlEventQuery();
    wql.EventClassName = "__InstanceModificationEvent";
    wql.WithinInterval = new TimeSpan( 0, 0, 1 );

    wql.Condition = String.Format( @"TargetInstance ISA 'Win32_LogicalDisk' and TargetInstance.DeviceId = '{0}'", this.m_logicalDrive );
    this.m_managementEventWatcher = new ManagementEventWatcher( scope, wql );

    //Register async. event handler
    /////////////////////////////////////////////////////////////
    this.m_managementEventWatcher.EventArrived += new EventArrivedEventHandler( mediaEvent.MediaEventArrived );
    this.m_managementEventWatcher.Start();
   } catch( Exception e ) {
    this.Exit();
    throw new Exception( "Media Check: "  + e.Message );
   }
  }

  /// <summary>Stops the monitoring of device.</summary>
  public void Exit( ) {
   //In case same class was called make sure only one instance is running
   /////////////////////////////////////////////////////////////
   if( null != this.m_managementEventWatcher ) {
    try {
     this.m_managementEventWatcher.Stop();
     this.m_managementEventWatcher = null;
    } catch {
    }
   }
  }
  /*-----------------------------------------------------------------------*/
  #endregion


  #region Helpers
  /*-----------------------------------------------------------------------*/

  private DriveStatus m_driveStatus = DriveStatus.Unknown;
  /// <summary>Triggers the event when change on device occured.</summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void MediaEventArrived( object sender, EventArrivedEventArgs e ) {
   // Get the Event object and display it
   PropertyData pd = e.NewEvent.Properties["TargetInstance"];
   DriveStatus driveStatus = this.m_driveStatus;
   if( pd != null ) {
    ManagementBaseObject mbo = pd.Value as ManagementBaseObject;
    System.IO.DriveInfo info = new System.IO.DriveInfo( (string)mbo.Properties["DeviceID"].Value );
    driveStatus = info.IsReady ? DriveStatus.Inserted : DriveStatus.Ejected;
   }

   if( driveStatus != this.m_driveStatus ){
    this.m_driveStatus = driveStatus;
    if( null != MediaWatcher ) {
     MediaWatcher( sender, driveStatus );
    }
   }
  }


  /// <summary>Gets the logical drive of a given path.</summary>
  /// <param name="path"></param>
  /// <returns></returns>
  private string GetLogicalDrive( string path ) {
   System.IO.DirectoryInfo dirInfo = new System.IO.DirectoryInfo( path );
   string root = dirInfo.Root.FullName;
   string logicalDrive = root.Remove( root.IndexOf( System.IO.Path.DirectorySeparatorChar ) );
   return logicalDrive;
  }
  /*-----------------------------------------------------------------------*/
  #endregion
 }
}

我在MSDN上发现了这个： http://social.msdn.microsoft.com/forums/en-US/csharpgeneral/thread/09912cee-4d2d-4efd-82a0-da20024b868b/

找出何时连接移除设备？

1 个答案: