包含vb.netu盘符的词条

vb.net编程接受U盘准备卸载用的windows消息 DBT_DEVICEQUERYREMOVE总是没反应，据说是因为默认注册的消息里

在我的XP+VB2010环境下，测试U盘插入拔出，没有问题：

Private WM_DEVICECHANGE As Integer = H219

Public Enum WM_DEVICECHANGE_WPPARAMS As Integer

DBT_CONFIGCHANGECANCELED = H19

DBT_CONFIGCHANGED = H18

DBT_CUSTOMEVENT = H8006

DBT_DEVICEARRIVAL = H8000

DBT_DEVICEQUERYREMOVE = H8001

DBT_DEVICEQUERYREMOVEFAILED = H8002

DBT_DEVICEREMOVECOMPLETE = H8004

DBT_DEVICEREMOVEPENDING = H8003

DBT_DEVICETYPESPECIFIC = H8005

DBT_DEVNODES_CHANGED = H7

DBT_QUERYCHANGECONFIG = H17

DBT_USERDEFINED = HFFFF

End Enum

Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)

If m.Msg = WM_DEVICECHANGE Then

Select Case m.WParam

Case WM_DEVICECHANGE_WPPARAMS.DBT_DEVICEARRIVAL

MsgBox("USB device is just plugged in!")

Case WM_DEVICECHANGE_WPPARAMS.DBT_DEVICEREMOVECOMPLETE

MsgBox("USB device is just taken out")

End Select

End If

MyBase.WndProc(m)

End Sub

相关问答

Q1: vb(vb.net)能不能修改计算机中指定驱动器的盘符？ 我想在U盘插入时通过序列号识别指定设备并

Sub RenameVolume()

'利用Shell函数在命令提示符下执行Diskpart命令的脚本，并存入日志文件

'达到替换逻辑盘符的目的

'在WindowsXp系统下测试成功

'获取临时文件路径

Temp = Environ("TEMP") "\"

'获取命令提示符路径

Cmd = Environ("ComSpec")

'设置脚本文件和日志文件路径

ScriptFile = Temp "DiskpartScript.txt"

ScriptLog = Temp "DiskpartScript.log"

'回车符和换行符

vbLfCr = vbLf vbCr

'脚本文件内容

'选择卷e

'移除盘符e

'分配盘符m

'退出Diskpart

ScriptTxt = "select volume e" vbLf vbCr _

"Remove letter = e" vbLf vbCr _

"assign letter = m" vbLf vbCr _

"exit" vbLf vbCr

'打开脚本文件并读取内容

Open ScriptFile For Output As #1

Print #1, ScriptTxt

Close #1

'打开错误处理

On Error Resume Next

'删除原有日志文件

Kill ScriptLog

'关闭错误处理

On Error GoTo 0

'执行脚本

ShellTxt = Cmd " /c ""diskpart.exe /S " ScriptFile " " ScriptLog """"

Shell ShellTxt

'打开错误处理

On Error Resume Next

Do

Err.Number = 0

'打开日志文件并读取内容，因日志文件存取速度慢，必须以锁定方式打开，否则会出错

Open ScriptLog For Input Lock Read Write As #1

DoEvents

Loop Until Err.Number = 0

'关闭错误处理

On Error GoTo 0

'日志文件中含有中文字符，必须以InputB函数以字节方式读取，否则长度会超出

LogTxt = InputB(LOF(1), #1)

Close #1

'转换以字节方式读取的日志文件内容

LogTxt = StrConv(LogTxt, vbUnicode)

'如果日志中出现两次成功，则认为执行成功，否则认为失败

If Len(LogTxt) - Len(Replace(LogTxt, "成功", "", 1)) = 4 Then

MsgBox "盘符替换成功！"

Else

MsgBox "盘符替换失败！"

End If

'删除临时文件

Kill ScriptFile

Kill ScriptLog

End Sub

Q2: vb.net 如何判断u盘是否接入

窗体上添加两个标签：Label1和Label2

下面代码经过VB 2005测试通过。

Imports System.IO

Public Class Form1

Public Const WM_DEVICECHANGE = H219

Public Const DBT_DEVICEARRIVAL = H8000

Public Const DBT_CONFIGCHANGECANCELED = H19

Public Const DBT_CONFIGCHANGED = H18

Public Const DBT_CUSTOMEVENT = H8006

Public Const DBT_DEVICEQUERYREMOVE = H8001

Public Const DBT_DEVICEQUERYREMOVEFAILED = H8002

Public Const DBT_DEVICEREMOVECOMPLETE = H8004

Public Const DBT_DEVICEREMOVEPENDING = H8003

Public Const DBT_DEVICETYPESPECIFIC = H8005

Public Const DBT_DEVNODES_CHANGED = H7

Public Const DBT_QUERYCHANGECONFIG = H17

Public Const DBT_USERDEFINED = HFFFF

Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)

If m.Msg = WM_DEVICECHANGE Then

Select Case m.WParam

Case WM_DEVICECHANGE

Case DBT_DEVICEARRIVAL 'U盘插入

Dim s() As DriveInfo = DriveInfo.GetDrives

For Each drive As DriveInfo In s

If drive.DriveType = DriveType.Removable Then

Label2.Text = "U盘已经插入！盘符为:" + drive.Name.ToString()

End If

Next

Case DBT_CONFIGCHANGECANCELED

Case DBT_CONFIGCHANGED

Case DBT_CUSTOMEVENT

Case DBT_DEVICEQUERYREMOVE

Case DBT_DEVICEQUERYREMOVEFAILED

Case DBT_DEVICEREMOVECOMPLETE 'U盘卸载

Label2.Text = "U盘已经拔出！"

Case DBT_DEVICEREMOVEPENDING

Case DBT_DEVICETYPESPECIFIC

Case DBT_DEVNODES_CHANGED

Case DBT_QUERYCHANGECONFIG

Case DBT_USERDEFINED

End Select

End If

MyBase.WndProc(m)

End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Label1.Text = "请操作U盘！"

Label2.Text = ""

End Sub

End Class

Q3: VB.NET检测插入U盘时执行某段代码，并能获取U盘盘符

以下内容为网络提供,但我自己验证可行,供你参考.

Imports System.IO

Public Class Form1

Public Const WM_DEVICECHANGE = H219

Public Const DBT_DEVICEARRIVAL = H8000

Public Const DBT_CONFIGCHANGECANCELED = H19

Public Const DBT_CONFIGCHANGED = H18

Public Const DBT_CUSTOMEVENT = H8006

Public Const DBT_DEVICEQUERYREMOVE = H8001

Public Const DBT_DEVICEQUERYREMOVEFAILED = H8002

Public Const DBT_DEVICEREMOVECOMPLETE = H8004

Public Const DBT_DEVICEREMOVEPENDING = H8003

Public Const DBT_DEVICETYPESPECIFIC = H8005

Public Const DBT_DEVNODES_CHANGED = H7

Public Const DBT_QUERYCHANGECONFIG = H17

Public Const DBT_USERDEFINED = HFFFF

Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)

If m.Msg = WM_DEVICECHANGE Then

Select Case m.WParam

Case WM_DEVICECHANGE

Case DBT_DEVICEARRIVAL 'U盘插入

ComboBox1.Items.Clear()

Dim s() As DriveInfo = DriveInfo.GetDrives

For Each drive As DriveInfo In s

If drive.DriveType = DriveType.Removable Then

ListBox1.Items.Add("U盘已插入！盘符为:" + drive.Name.ToString())

ComboBox1.Items.Add(drive.Name)

End If

Next

BtnWrite.Enabled = True

BtnRead.Enabled = True

Case DBT_CONFIGCHANGECANCELED

Case DBT_CONFIGCHANGED

Case DBT_CUSTOMEVENT

Case DBT_DEVICEQUERYREMOVE

Case DBT_DEVICEQUERYREMOVEFAILED

Case DBT_DEVICEREMOVECOMPLETE 'U盘卸载

ListBox1.Items.Add("U盘卸载！")

BtnWrite.Enabled = False

BtnRead.Enabled = False

Case DBT_DEVICEREMOVEPENDING

Case DBT_DEVICETYPESPECIFIC

Case DBT_DEVNODES_CHANGED

Case DBT_QUERYCHANGECONFIG

Case DBT_USERDEFINED

End Select

End If

MyBase.WndProc(m)

End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

ListBox1.Items.Add("请您现在插入U盘至USB接口！")

End Sub

Private Sub BtnWrite_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnWrite.Click

If ComboBox1.Text = "" Then

MsgBox("请选择U盘盘符！", MsgBoxStyle.Exclamation, "Warn")

Else

Dim Writer As StreamWriter = Nothing

Try

Dim fileName As String = ComboBox1.Text + "Test.txt"

Writer = New StreamWriter(fileName)

Writer.WriteLine(InputBox("老四，请输入要保存的字符串", "输入信息", "Input then Test String! hehe!"))

MsgBox("Write to " + fileName + " Success!")

Catch ex As Exception

MsgBox(ex.Message, MsgBoxStyle.Critical, "Write 失败")

Finally

If Writer IsNot Nothing Then Writer.Close()

End Try

End If

End Sub

Private Sub BtnRead_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnRead.Click

If ComboBox1.Text = "" Then

MsgBox("请选择U盘盘符！", MsgBoxStyle.Exclamation, "Warn")

Else

Dim Reader As StreamReader = Nothing

Try

Dim fileName As String = ComboBox1.Text + "Test.txt"

Reader = New StreamReader(fileName)

MsgBox("Read from " + fileName + vbCrLf + Reader.ReadToEnd, MsgBoxStyle.Information, "Info")

Catch ex As Exception

MsgBox(ex.Message, MsgBoxStyle.Critical, "Read 失败")

Finally

If Reader IsNot Nothing Then Reader.Close()

End Try

End If

End Sub

End Class

Q4: 关于 VB.NET 2008中U盘的插拔

一下代码将自动完成检测：

Imports System.IO

Public Class Form1

Public Const WM_DEVICECHANGE = H219

Public Const DBT_DEVICEARRIVAL = H8000

Public Const DBT_DEVICEREMOVECOMPLETE = H8004

Dim DriveLetter As String

Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)

If m.Msg = WM_DEVICECHANGE Then

Select Case m.WParam

Case DBT_DEVICEARRIVAL

Dim s() As DriveInfo = DriveInfo.GetDrives

For Each drive As DriveInfo In s

If drive.DriveType = DriveType.Removable Then

DriveLetter = drive.Name.ToString()

Debug.WriteLine("U盘 :" DriveLetter "已插入.")

End If

Next

Case DBT_DEVICEREMOVECOMPLETE

Dim s() As DriveInfo = DriveInfo.GetDrives

For Each drive As DriveInfo In s

If drive.ToString = DriveLetter Then Exit Sub

Next

Debug.WriteLine("U盘:" DriveLetter "已卸载！")

End Select

End If

MyBase.WndProc(m)

End Sub

End Class