U盘加载，卸载，拔出，插入（转载）

U盘加载，卸载，拔出，插入，WM_DEVICECHANGE，WndProc，DBT_DEVICEARRIVAL，DBT_DEVICEREMOVECOMPLETE

2008-08-22 14:42 by virus, 4161 visits, 网摘, 收藏, 编辑 最近在做一个和U盘有关的项目，有一个需求是要求显示插入的U盘的盘符，当然了，如果拔出U盘，也应该更新显示，就是显示U口上插入的全部移动设备的全部盘符。 其实就是重写 protected   override   void  WndProc( ref  Message m) 方法，根据得到的系统消息来处理，但是如果要实时更新的话，最好加上定时查询U口设备，将查询结果更新，时间的间隔可以自己定义，根据项目情况吧。 下面是完整的代码，如果大家有什么好的建议，欢迎大家一起交流。 using  System; using  System.Collections.Generic; using  System.ComponentModel; using  System.Data; using  System.Drawing; using  System.Text; using  System.IO; using  System.Windows.Forms; using  System.Threading; namespace  WindowsApp{     public   partial   class  ComboBoxForm2 : Form    {         private  IList < string >  diskList  =   new  List < string > ();         delegate   void  SetTextCallback( string  s);         delegate   void  ClearListBoxItem();         private  Thread thread  =   null ;         private  BackgroundWorker backgroundworker;         public  ComboBoxForm2()        {            InitializeComponent();        }         protected   override   void  WndProc( ref  Message m)        {             object  ojb  =   new   object ();             try             {                 // WM_DEVICECHANGE，系统硬件改变发出的系统消息                  if  (m.Msg  ==  WndProMsgConst.WM_DEVICECHANGE)                {                     switch  (m.WParam.ToInt32())                    {                         case  WndProMsgConst.WM_DEVICECHANGE:                             break ;                         // DBT_DEVICEARRIVAL，设备检测结束，并且可以使用                          case  WndProMsgConst.DBT_DEVICEARRIVAL:                            scanUDisk();                            listBox1.Items.Clear();                            foreach  ( string  s  in  diskList)            {                listBox1.Items.Add(s);            }                             break ;                         // DBT_DEVICEREMOVECOMPLETE,设备卸载或者拔出                          case  WndProMsgConst.DBT_DEVICEREMOVECOMPLETE:                            scanUDisk();                            listBox1.Items.Clear();                             foreach  ( string  s  in  diskList)                            {                                listBox1.Items.Add(s);                            }                             break ;                                           }                }            }             catch  (Exception ex)            {                MessageBox.Show( " 当前盘不能正确识别，请重新尝试！ " ,  " 提示 " , MessageBoxButtons.OK, MessageBoxIcon.Information);            }             base .WndProc( ref  m);        }         private   void  button1_Click( object  sender, EventArgs e)        {            IList < string >  diskList  =   new  List < string > ();            diskList.Add( " k001 " );            diskList.Add( " k002 " );            diskList.Add( " k003 " );            diskList.Add( " k004 " );            comboBox1.DataSource  =  diskList;        }         ///   <summary>          ///  扫描U口设备         ///   </summary>          ///   <param name="obj"></param>          private   void  scanUDisk()        {            diskList.Clear();            DriveInfo[] drives  =  DriveInfo.GetDrives();             foreach  (DriveInfo drive  in  drives)            {                 if  ((drive.DriveType  ==  DriveType.Removable)  &&   ! drive.Name.Substring( 0 ,  1 ).Equals( " A " ))                {                     try                     {                        diskList.Add(drive.Name);                    }                     catch                     {                        MessageBox.Show( " 当前盘不能正确识别，请重新尝试！ " ,  " 提示 " , MessageBoxButtons.OK, MessageBoxIcon.Information);                    }                }            }        }         private   void  ComboBoxForm2_Load( object  sender, EventArgs e)        {            System.Timers.Timer timer  =   new  System.Timers.Timer( 1000 );            timer.Enabled  =   true ;            timer.Elapsed  +=   new  System.Timers.ElapsedEventHandler(fi);            timer.AutoReset  =   true ;                    }                private   void  ThreadProcSafe()        {            scanUDisk();             // MessageBox.Show(diskList.Count.ToString());              foreach  ( string  s  in  diskList)            {                SetText(s);            }        }         public   void  SetText( string  text)        {             if  ( this .listBox1.InvokeRequired)            {                 if  (listBox1.Items.Contains(text))                     return ;                SetTextCallback d  =   new  SetTextCallback(SetText);                 this .Invoke(d,  new   object [] { text });            }             else             {                 if  (listBox1.Items.Contains(text))                     return ;                 this .listBox1.Items.Add(text);            }        }         void  fi( object  sender, System.Timers.ElapsedEventArgs e)        {            scanUDisk();             // listBox1.Items.Clear();              foreach  ( string  s  in  diskList)            {                SetText(s);            }        }    }     ///   <summary>      ///  windows消息的常量     ///   </summary>      class  WndProMsgConst    {         #region  WndProc常量          public   const   int  WM_DEVICECHANGE  =   0x219 ;         public   const   int  DBT_DEVICEARRIVAL  =   0x8000 ;         public   const   int  DBT_CONFIGCHANGECANCELED  =   0x0019 ;         public   const   int  DBT_CONFIGCHANGED  =   0x0018 ;         public   const   int  DBT_CUSTOMEVENT  =   0x8006 ;         public   const   int  DBT_DEVICEQUERYREMOVE  =   0x8001 ;         public   const   int  DBT_DEVICEQUERYREMOVEFAILED  =   0x8002 ;         public   const   int  DBT_DEVICEREMOVECOMPLETE  =   0x8004 ;         public   const   int  DBT_DEVICEREMOVEPENDING  =   0x8003 ;         public   const   int  DBT_DEVICETYPESPECIFIC  =   0x8005 ;         public   const   int  DBT_DEVNODES_CHANGED  =   0x0007 ;         public   const   int  DBT_QUERYCHANGECONFIG  =   0x0017 ;         public   const   int  DBT_USERDEFINED  =   0xFFFF ;         #endregion     }}设备的实时性还是差一点，还有啊，像这样的窗体有很多，我不能每个窗体都copy一遍这些代码吧，如何封装起来呢，控件的线程安全也是问题，还需要改进啊，谁有好的意见可以提出来。msn:jorden008@hotmail.commail:jorden008@163.com 简单封装了一下，封装类如下： using  System; using  System.Collections.Generic; using  System.Text; using  System.Windows.Forms; using  System.Threading; using  System.IO; namespace  WindowsApp{     class  Class1    {         private  IList < string >  diskList  =   new  List < string > ();         delegate   void  SetTextCallback( string  s);         delegate   void  ClearListBoxItem();         private  ListBox _listbox;         private  Form _form;         private  Thread thread  =   null ;         // private BackgroundWorker backgroundworker;          public  Class1()        {            System.Timers.Timer timer  =   new  System.Timers.Timer( 1000 );            timer.Enabled  =   true ;            timer.Elapsed  +=   new  System.Timers.ElapsedEventHandler(fi);            timer.AutoReset  =   true ;        }         public   void  filldata(Form form, Message m,ListBox listbox)        {            _listbox  =  listbox;            _form  =  form;             try             {                 // WM_DEVICECHANGE，系统硬件改变发出的系统消息                  if  (m.Msg  ==  WndProMsgConst.WM_DEVICECHANGE)                {                     switch  (m.WParam.ToInt32())                    {                         case  WndProMsgConst.WM_DEVICECHANGE:                             break ;                         // DBT_DEVICEARRIVAL，设备检测结束，并且可以使用                          case  WndProMsgConst.DBT_DEVICEARRIVAL:                            scanUDisk();                            _listbox.Items.Clear();                             foreach  ( string  s  in  diskList)                            {                                _listbox.Items.Add(s);                            }                             break ;                         // DBT_DEVICEREMOVECOMPLETE,设备卸载或者拔出                          case  WndProMsgConst.DBT_DEVICEREMOVECOMPLETE:                            scanUDisk();                            _listbox.Items.Clear();                             foreach  ( string  s  in  diskList)                            {                                _listbox.Items.Add(s);                            }                             break ;                    }                }            }             catch  (Exception ex)            {                MessageBox.Show( " 当前盘不能正确识别，请重新尝试！ " ,  " 提示 " , MessageBoxButtons.OK, MessageBoxIcon.Information);            }        }         public   void  SetText( string  text)        {             if  ( this ._listbox.InvokeRequired)            {                 if  (_listbox.Items.Contains(text))                     return ;                SetTextCallback d  =   new  SetTextCallback(SetText);                _form.Invoke(d,  new   object [] { text });            }             else             {                 if  (_listbox.Items.Contains(text))                     return ;                 this ._listbox.Items.Add(text);            }        }         void  fi( object  sender, System.Timers.ElapsedEventArgs e)        {            scanUDisk();             // listBox1.Items.Clear();              foreach  ( string  s  in  diskList)            {                SetText(s);            }        } ///   <summary>          ///  扫描U口设备         ///   </summary>          ///   <param name="obj"></param>          private   void  scanUDisk()        {            diskList.Clear();            DriveInfo[] drives  =  DriveInfo.GetDrives();             foreach  (DriveInfo drive  in  drives)            {                 if  ((drive.DriveType  ==  DriveType.Removable)  &&   ! drive.Name.Substring( 0 ,  1 ).Equals( " A " ))                {                     try                     {                        diskList.Add(drive.Name);                    }                     catch                     {                        MessageBox.Show( " 当前盘不能正确识别，请重新尝试！ " ,  " 提示 " , MessageBoxButtons.OK, MessageBoxIcon.Information);                    }                }            }        }    }  ///   <summary>      ///  windows消息的常量     ///   </summary>      class  WndProMsgConst    {         #region  WndProc常量          public   const   int  WM_DEVICECHANGE  =   0x219 ;         public   const   int  DBT_DEVICEARRIVAL  =   0x8000 ;         public   const   int  DBT_CONFIGCHANGECANCELED  =   0x0019 ;         public   const   int  DBT_CONFIGCHANGED  =   0x0018 ;         public   const   int  DBT_CUSTOMEVENT  =   0x8006 ;         public   const   int  DBT_DEVICEQUERYREMOVE  =   0x8001 ;         public   const   int  DBT_DEVICEQUERYREMOVEFAILED  =   0x8002 ;         public   const   int  DBT_DEVICEREMOVECOMPLETE  =   0x8004 ;         public   const   int  DBT_DEVICEREMOVEPENDING  =   0x8003 ;         public   const   int  DBT_DEVICETYPESPECIFIC  =   0x8005 ;         public   const   int  DBT_DEVNODES_CHANGED  =   0x0007 ;         public   const   int  DBT_QUERYCHANGECONFIG  =   0x0017 ;         public   const   int  DBT_USERDEFINED  =   0xFFFF ;         #endregion     }} 使用方法如下： using  System; using  System.Collections.Generic; using  System.ComponentModel; using  System.Data; using  System.Drawing; using  System.Text; using  System.IO; using  System.Windows.Forms; using  System.Threading; namespace  WindowsApp{     public   partial   class  ComboBoxForm2 : Form    {         public  ComboBoxForm2()        {            InitializeComponent();        }         protected   override   void  WndProc( ref  Message m)        {            Class1 c = new  Class1();            c.filldata( this ,m, listBox1);                         base .WndProc( ref  m);        }           }   }   转载自： http://www.cnblogs.com/virusswb/archive/2008/08/22/1274085.html

转载于:https://www.cnblogs.com/wuhenke/archive/2010/05/07/1730039.html

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