usb插入/拔出系统和其他操作 [英] usb plugged/unplugged from the system and other actions

问题描述

我的应用是在任何USB设备从系统插入或拔出时发送电子邮件。我使用ManagementEventWatcher来捕获此类事件。毫无疑问，我们遇到了一些情况，即usb驱动器出现了问题，并且它在某种程度上从系统中消失了
（不是物理上未插入）。我们没有注意到任何通知意味着事件似乎不在我们已经使用的内容之下。有什么东西我可以添加到我的应用程序来处理其他事情，而不是像usb
电源问题或其他任何相关的插件/拔出？请参阅下面的代码：

I have appliction that send email when any of usb devices is plugged or unplugged from the system. I use ManagementEventWatcher to catch such event. Neverthless we faced some situation that there was something wrong with usb drive and it was somehow dissapered from the system (not physically unplugged). We haven't noticed any notification means it seems that event is not under what we already using. Is there anything that i could add to my application to handle other things instead of justus plug/unplug like usb power issue or whatever else regarding that? See my code below:

Imports System.Management

Public Class Usb
    Public Event ReportEvent(information As String)
    Private WithEvents _mediaConnectWatcher As ManagementEventWatcher 
    Private _usbDriveName As String
    Private _uUsbDriveLetter As String

    Private Enum InterfaceDriveType
        Usb
    End Enum

    Private Async Function StartDetection() As Task
            ' __InstanceOperationEvent will trap both Creation and Deletion of class instances
            Dim query2 As New WqlEventQuery("SELECT * FROM __InstanceOperationEvent WITHIN 1 " _
                                            & "WHERE TargetInstance ISA 'Win32_DiskDrive'")

        _mediaConnectWatcher = New ManagementEventWatcher
        _mediaConnectWatcher.Query = query2

            'AddHandler  _mMediaConnectWatcher.EventArrived, AddressOf Arrived
            Dim t As Task= Task.Run(sub() _mediaConnectWatcher.Start())    
            Await t          
    End Function

    Public sub Arrived(sender As Object, e As EventArrivedEventArgs) Handles _mediaConnectWatcher.EventArrived
        Try
            'If InvokeRequired Then
            '    Invoke(New Action(Of Object, EventArrivedEventArgs)(AddressOf Arrived), sender, e)
            'Else
            Dim mbo, obj As ManagementBaseObject
            'the first thing we have to do is figure out if this is a creation or deletion event
            mbo = e.NewEvent
            'next we need a copy of the instance that was either created or deleted
            obj = CType(mbo("TargetInstance"), ManagementBaseObject)

         

推荐答案

JimmyJimm，

Hi JimmyJimm,

谢谢你r发布在这里。

对于你的问题，你可以尝试下面的代码。

For your question, you could try the code below.

Imports System.Management ' Also had to add System.Management as a reference

Public Class Form1

    Private WithEvents m_MediaConnectWatcher As ManagementEventWatcher
    Public USBDriveName As String
    Public USBDriveLetter As String

    Public Sub StartDetection()
        ' __InstanceOperationEvent will trap both Creation and Deletion of class instances
        Dim query2 As New WqlEventQuery("SELECT * FROM __InstanceOperationEvent WITHIN 1 " _
  & "WHERE TargetInstance ISA 'Win32_DiskDrive'")

        m_MediaConnectWatcher = New ManagementEventWatcher
        m_MediaConnectWatcher.Query = query2
        m_MediaConnectWatcher.Start()
    End Sub


    Private Sub Arrived(ByVal sender As Object, ByVal e As System.Management.EventArrivedEventArgs) Handles m_MediaConnectWatcher.EventArrived

        Dim mbo, obj As ManagementBaseObject

        ' the first thing we have to do is figure out if this is a creation or deletion event
        mbo = CType(e.NewEvent, ManagementBaseObject)
        ' next we need a copy of the instance that was either created or deleted
        obj = CType(mbo("TargetInstance"), ManagementBaseObject)

        Select Case mbo.ClassPath.ClassName
            Case "__InstanceCreationEvent"
                If obj("InterfaceType") = "USB" Then
                    MsgBox(obj("Caption") & " (Drive letter " & GetDriveLetterFromDisk(obj("Name")) & ") has been plugged in")
                Else
                    MsgBox(obj("InterfaceType"))
                End If
            Case "__InstanceDeletionEvent"
                If obj("InterfaceType") = "USB" Then
                    MsgBox(obj("Caption") & " has been unplugged")
                    If obj("Caption") = USBDriveName Then
                        USBDriveLetter = ""
                        USBDriveName = ""
                    End If
                Else
                    MsgBox(obj("InterfaceType"))
                End If
            Case Else
                MsgBox("nope: " & obj("Caption"))
        End Select
    End Sub

    Private Function GetDriveLetterFromDisk(ByVal Name As String) As String
        Dim oq_part, oq_disk As ObjectQuery
        Dim mos_part, mos_disk As ManagementObjectSearcher
        Dim obj_part, obj_disk As ManagementObject
        Dim ans As String = ""

        ' WMI queries use the "\" as an escape charcter
        Name = Replace(Name, "\", "\\")

        ' First we map the Win32_DiskDrive instance with the association called
        ' Win32_DiskDriveToDiskPartition. Then we map the Win23_DiskPartion
        ' instance with the assocation called Win32_LogicalDiskToPartition

        oq_part = New ObjectQuery("ASSOCIATORS OF {Win32_DiskDrive.DeviceID=""" & Name & """} WHERE AssocClass = Win32_DiskDriveToDiskPartition")
        mos_part = New ManagementObjectSearcher(oq_part)
        For Each obj_part In mos_part.Get()

            oq_disk = New ObjectQuery("ASSOCIATORS OF {Win32_DiskPartition.DeviceID=""" & obj_part("DeviceID") & """} WHERE AssocClass = Win32_LogicalDiskToPartition")
            mos_disk = New ManagementObjectSearcher(oq_disk)
            For Each obj_disk In mos_disk.Get()
                ans &= obj_disk("Name") & ","
            Next
        Next

        Return ans.Trim(","c)
    End Function

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

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        m_MediaConnectWatcher.Stop()
        Application.Exit()
    End Sub

End Class

最好的问候，

Wendy

这篇关于usb插入/拔出系统和其他操作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！