如何检查给定的USB设备是否已插入？

我们的winforms应用程序使用制造商的SDK支持自定义控制器，但不支持检测设备是否存在。 如何检查给定的USB设备是否已插入？

Answer 1

以下类用于监视设备，您可以使用它来检测USB设备。

using System; using System.Collections.Generic; using System.Text; using System.Management; namespace DeviceMonitor.Event { /// 
Media watcher delegate.
 ///  ///  public delegate void MediaWatcherEventHandler(object sender, DeviceMonitor.Event.MediaEvent.DriveStatus driveStatus ); /// 
Class to monitor devices.
 public class MediaEvent { #region Variables /*------------------------------------------------------------------------*/ private string m_logicalDrive; private ManagementEventWatcher m_managementEventWatcher = null; /*------------------------------------------------------------------------*/ #endregion #region Events /*------------------------------------------------------------------------*/ public event MediaWatcherEventHandler MediaWatcher; /*------------------------------------------------------------------------*/ #endregion #region Enums /*------------------------------------------------------------------------*/ /// 
The drive types.
 public enum DriveType { Unknown = 0, NoRootDirectory = 1, RemoveableDisk = 2, LocalDisk = 3, NetworkDrive = 4, CompactDisk = 5, RamDisk = 6 } /// 
The drive status.
 public enum DriveStatus { Unknown = -1, Ejected = 0, Inserted = 1, } /*-----------------------------------------------------------------------*/ #endregion #region Monitoring /*-----------------------------------------------------------------------*/ /// 
Starts the monitoring of device.
 ///  ///  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 ); } } /// 
Stops the monitoring of device.
 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; /// 
Triggers the event when change on device occured.
 ///  ///  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 ); } } } /// 
Gets the logical drive of a given path.
 ///  ///  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 } } 

编辑

摘自http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/09912cee-4d2d-4efd-82a0-da20024b868b