VB如何退出U盘

2008-10-20 05:30:19 701 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

vb.net的UI设计对UI设计我们应该不陌生了,自己做过几个小系统,像学生管理系统、机房收费系统等都是客户端模式，当然还有我们的牛腩新闻发布系统，这是我们第一次接触的比较正规的web系统。现在就vb.net的一些UI设计小技巧给大家做个总结，希望对我们的重构或合作都有所帮助吧。合作的时候我是负责U层的，所以设计这里就要尽可能的想到“全心全意为人民服务”。因为用户使用的时候就是跟页面交互嘛，阅读详情

VB如何编程退出U盘
本人想程序控制退出U盘设备
请高手指点

...全文

VB（视频缓冲区）配置 1.申请缓冲池把地址给打出来利用相关数据结构和API实操（1）.设置缓冲池的信息用到的API参考海思提供sample代码 VB_CONF_S HI_MPI_VB_SetConfig HI_MPI_VB_Init （2）.初始化（3）.获取地址（4）.退出设置缓冲池信息主要是配置VB_CONFIG_S结构体，必须包含hi_comm_vb.h、mpi_vb.h 头文件。 (1).VB_POOL_CONFIG_S的第3个参数hiVB_REMAP_MODE_E是枚举类型，hiVB_ 阅读详情

huangyahai

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切换为时间正序

bob008 2008-10-21

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MARK

tanjiunnya 2008-10-21

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'Form
Option Explicit

Private Sub Command2_Click(Index As Integer)

Dim sDrive As String

If List1.ListIndex > -1 Then

sDrive = List1.List(List1.ListIndex)

Select Case Index
Case 0
Call DeviceSetMedia(sDrive, IOCTL_STORAGE_EJECT_MEDIA)
Case 1
Call DeviceSetMedia(sDrive, IOCTL_STORAGE_LOAD_MEDIA)
End Select

End If

End Sub

tanjiunnya 2008-10-21

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'Module

Option Explicit

Public Const IOCTL_STORAGE_EJECT_MEDIA As Long = &H2D4808
Public Const IOCTL_STORAGE_LOAD_MEDIA As Long = &H2D480C

Public Function DeviceSetMedia(sDrive As String, ctrlCode As Long) As Boolean

Dim hDevice As Long
Dim bytesReturned As Long
Dim success As Long

'the drive letter has to be passed
'without a trailing slash (ie 'G:')
sDrive = UnQualifyPath(sDrive)

'obtain a handle to the device
hDevice = CreateFile("\\.\" & sDrive, _
GENERIC_READ, _
FILE_SHARE_READ Or FILE_SHARE_WRITE, _
ByVal 0&, _
OPEN_EXISTING, _
0&, 0&)

If hDevice <> INVALID_HANDLE_VALUE Then

'If the operation succeeds,
'DeviceIoControl returns zero
success = DeviceIoControl(hDevice, _
ctrlCode, _
0&, _
0&, _
ByVal 0&, _
0&, _
bytesReturned, _
ByVal 0&)

End If

Call CloseHandle(hDevice)
DeviceSetMedia = success <> 0

End Function

东方之珠 2008-10-21

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这儿有简单的。http://blog.csdn.net/chenhui530/archive/2007/12/13/1932917.aspx

huangyahai 2008-10-20

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谢谢楼上的朋友
不过好复杂，本人初学者
卸载U盘竟然要这么复杂
好好学习中

yinweihong 2008-10-20

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http://support.microsoft.com/default.aspx?scid=kb;en-us;165721 C的

yinweihong 2008-10-20

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Option Explicit

Dim boTimeOut As Boolean



Private Const DRIVE_CDROM As Long = 5

Private Const DRIVE_REMOVABLE As Long = 2



Private Const GENERIC_READ As Long = &H80000000

Private Const GENERIC_WRITE As Long = &H40000000



Private Const OPEN_EXISTING As Long = 3

Private Const FILE_DEVICE_FILE_SYSTEM As Long = 9

Private Const FILE_DEVICE_MASS_STORAGE As Long = &H2D&

Private Const METHOD_BUFFERED As Long = 0

Private Const FILE_ANY_ACCESS As Long = 0

Private Const FILE_READ_ACCESS As Long = 1

Private Const LOCK_VOLUME As Long = 6

Private Const DISMOUNT_VOLUME As Long = 8

Private Const EJECT_MEDIA As Long = &H202

Private Const MEDIA_REMOVAL As Long = &H201

Private Const INVALID_HANDLE_VALUE As Long = -1



Private Const LOCK_TIMEOUT As Long = 1000

Private Const LOCK_RETRIES As Long = 20



Private Declare Function GetDriveType Lib "kernel32.dll" _

            Alias "GetDriveTypeA" _

            (ByVal nDrive As String) As Long

        

Private Declare Function CloseHandle Lib "kernel32.dll" _

            (ByVal hObject As Long) As Long



Private Declare Function CreateFile Lib "kernel32.dll" Alias "CreateFileA" _

            (ByVal lpFileName As String, _

             ByVal dwDesiredAccess As Long, _

             ByVal dwShareMode As Long, _

             ByRef lpSecurityAttributes As Long, _

             ByVal dwCreationDisposition As Long, _

             ByVal dwFlagsAndAttributes As Long, _

             ByVal hTemplateFile As Long) As Long

             

Private Declare Function DeviceIoControl Lib "kernel32.dll" _

            (ByVal hDevice As Long, _

             ByRef dwIoControlCode As Long, _

             ByRef lpInBuffer As Any, _

             ByVal nInBufferSize As Long, _

             ByRef lpOutBuffer As Any, _

             ByVal nOutBufferSize As Long, _

             ByRef lpBytesReturned As Long, _

             ByRef lpOverlapped As Long) As Long

Private Function CTL_CODE(lngDevFileSys As Long, lngFunction As Long, _

              lngMethod As Long, lngAccess As Long) As Long

CTL_CODE = (lngDevFileSys * (2 ^ 16)) Or (lngAccess * (2 ^ 14)) Or (lngFunction * (2 ^ 2)) Or lngMethod

End Function



Private Function OpenVolume(strLetter As String, lngVolHandle As Long) As Boolean

Dim lngDriveType As Long

Dim lngAccessFlags As Long

Dim strVolume As String

lngDriveType = GetDriveType(strLetter)

Select Case lngDriveType

    Case DRIVE_REMOVABLE

        lngAccessFlags = GENERIC_READ Or GENERIC_WRITE

    Case DRIVE_CDROM

        lngAccessFlags = GENERIC_READ

    Case Else

        OpenVolume = False

        Exit Function

End Select

strVolume = "\\.\" & strLetter

lngVolHandle = CreateFile(strVolume, lngAccessFlags, 0, _

                ByVal CLng(0), OPEN_EXISTING, ByVal CLng(0), ByVal CLng(0))

If lngVolHandle = INVALID_HANDLE_VALUE Then

    OpenVolume = False

    Exit Function

End If

OpenVolume = True

End Function



Private Function CloseVolume(lngVolHandle As Long) As Boolean

Dim lngReturn As Long

lngReturn = CloseHandle(lngVolHandle)

If lngReturn = 0 Then

    CloseVolume = False

Else

    CloseVolume = True

End If

End Function



Private Function LockVolume(ByRef lngVolHandle As Long) As Boolean

Dim lngBytesReturned As Long

Dim intCount As Integer

Dim intI As Integer

Dim boLocked As Boolean

Dim lngFunction As Long

lngFunction = CTL_CODE(FILE_DEVICE_FILE_SYSTEM, LOCK_VOLUME, METHOD_BUFFERED, FILE_ANY_ACCESS)

intCount = LOCK_TIMEOUT / LOCK_RETRIES

boLocked = False

For intI = 0 To LOCK_RETRIES

    boTimeOut = False

    Timer1.Interval = intCount

    Timer1.Enabled = True

    Do Until boTimeOut = True Or boLocked = True

        boLocked = DeviceIoControl(lngVolHandle, ByVal lngFunction, _

                    CLng(0), 0, CLng(0), 0, lngBytesReturned, ByVal CLng(0))

        DoEvents

    Loop

    If boLocked = True Then

        LockVolume = True

        Timer1.Enabled = False

        Exit Function

    End If

Next intI

LockVolume = False

End Function

Private Function DismountVolume(lngVolHandle As Long) As Boolean

Dim lngBytesReturned As Long

Dim lngFunction As Long

lngFunction = CTL_CODE(FILE_DEVICE_FILE_SYSTEM, DISMOUNT_VOLUME, METHOD_BUFFERED, FILE_ANY_ACCESS)

DismountVolume = DeviceIoControl(lngVolHandle, ByVal lngFunction, _

                    0, 0, 0, 0, lngBytesReturned, ByVal 0)

End Function

Private Function PreventRemovalofVolume(lngVolHandle As Long) As Boolean

Dim boPreventRemoval As Boolean

Dim lngBytesReturned As Long

Dim lngFunction As Long

boPreventRemoval = False

lngFunction = CTL_CODE(FILE_DEVICE_MASS_STORAGE, MEDIA_REMOVAL, METHOD_BUFFERED, FILE_READ_ACCESS)

PreventRemovalofVolume = DeviceIoControl(lngVolHandle, ByVal lngFunction, _

                        boPreventRemoval, Len(boPreventRemoval), 0, 0, lngBytesReturned, ByVal 0)

End Function

Private Function AutoEjectVolume(lngVolHandle As Long) As Boolean

Dim lngFunction As Long

Dim lngBytesReturned As Long

lngFunction = CTL_CODE(FILE_DEVICE_MASS_STORAGE, EJECT_MEDIA, METHOD_BUFFERED, FILE_READ_ACCESS)

AutoEjectVolume = DeviceIoControl(lngVolHandle, ByVal lngFunction, _

                    0, 0, 0, 0, lngBytesReturned, ByVal 0)

End Function



Private Sub Eject(strVol As String)

Dim lngVolHand As Long

Dim boResult As Boolean

Dim boSafe As Boolean

strVol = strVol & ":"

'

' Open and get a Handle for the Volume

'

boResult = OpenVolume(strVol, lngVolHand)

If boResult = False Then

    MsgBox "Error Opening Volume " & Err.LastDllError

    Exit Sub

End If

'

' Lock the Volume

'

boResult = LockVolume(lngVolHand)

If boResult = False Then

    MsgBox "Error Dismounting Volume " & Err.LastDllError

    CloseVolume (lngVolHand)

    Exit Sub

End If

'

'Dismount the Volume

'

boResult = DismountVolume(lngVolHand)

If boResult = False Then

    MsgBox "Error Dismounting Volume " & Err.LastDllError

    CloseVolume (lngVolHand)

    Exit Sub

End If

'

' Set to allow the Volume to be Removed

'

boResult = PreventRemovalofVolume(lngVolHand)

If boResult = False Then

    MsgBox "Error Allowing Removal of Volume " & Err.LastDllError

    CloseVolume (lngVolHand)

    Exit Sub

End If

boSafe = True

'

' Eject the Volume

'

boResult = AutoEjectVolume(lngVolHand)

If boSafe = True Then

    MsgBox "Media may be Safely Removed from Drive " & UCase(strVol)

End If

'

' Close the Handle

'

boResult = CloseVolume(lngVolHand)

If boResult = False Then

    MsgBox "Error Closing Volume " & Err.LastDllError

    Exit Sub

End If

Unload Me

End Sub



Private Sub Timer1_Timer()

boTimeOut = True

End Sub

It's called by 



Code:

Call Eject(drive letter without the colon)

huangyahai 2008-10-20

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有没有高手指点下哦。。。。

VB如何退出U盘

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