Service app not getting SystemEvents.SessionSwitch

[threeeye]

Hi guys,
My Service app is almost ready, but I have a little problem...
As everyone knows, a Service can't interact with a GUI (for security reasons), but it also can't interact with SystemEvents.SessionSwitch
That is the problem...
I need my service to detect a login or logoff event.
I found a post (don't remember where) that said you can do it with a Hidden Form, but I can't get it to work...
Here is my Service Onstart:

        Protected Overrides Sub OnStart(args() As String)
            ' Add code here to start your service. This method should set things
            ' in motion so your service can do its work.

            'Connect to Server
            Connect()


            EventLog.WriteEntry("PCMonitor", "Starting PCMonitor")
            Dim t As New Thread(AddressOf RunMessagePump)
            t.Start()

        End Sub

        Sub RunMessagePump()
        EventLog.WriteEntry("PCMonitor.MessagePump", "Starting PCMonitor Message Pump")
        Application.Run(New HiddenForm())
        End Sub

Here is my "Hidden Form":

Imports Microsoft.Win32
Imports System.ComponentModel
Imports System.Configuration.Install
Imports System.ServiceProcess
Imports System.Threading
Imports System.Windows.Forms

Partial Class HiddenForm
    Inherits Form

    Public Sub New()
        InitializeComponent()
    End Sub

    Private Sub HiddenForm_Load(sender As Object, e As EventArgs)
        AddHandler SystemEvents.TimeChanged, AddressOf SystemEvents_TimeChanged
        AddHandler SystemEvents.UserPreferenceChanged, AddressOf SystemEvents_UPCChanged
        AddHandler SystemEvents.SessionSwitch, AddressOf SystemEvents_SessionSwitch
        'AddHandler SystemEvents.SessionEnded, AddressOf SystemEvents_SessionEnded
    End Sub

    Private Sub HiddenForm_FormClosing(sender As Object, e As FormClosingEventArgs)
        RemoveHandler SystemEvents.TimeChanged, New EventHandler(AddressOf SystemEvents_TimeChanged)
        RemoveHandler SystemEvents.UserPreferenceChanged, New UserPreferenceChangedEventHandler(AddressOf SystemEvents_UPCChanged)
        RemoveHandler SystemEvents.SessionSwitch, New SessionSwitchEventHandler(AddressOf SystemEvents_SessionSwitch)
    End Sub
    Private Sub SystemEvents_SessionSwitch(sender As Object, e As SessionSwitchEventArgs)
        EventLog.WriteEntry("PCMonitor.SessionSwitch", e.Reason.ToString)
        'Dim FILE_NAME As String = "C:\Program Files\PCMonitor-Client\Notify\cmd.txt"

        'If File.Exists(FILE_NAME) = True Then

        '    Dim objWriter As New StreamWriter(FILE_NAME)

        '    objWriter.Write(e.Reason.ToString)
        '    objWriter.Close()
        'End If

        Select Case e.Reason
            Case SessionSwitchReason.SessionLogoff
                Thread.Sleep(1000)
                PCMonitor.SendInfo(PCMonitor.GetString())
            Case SessionSwitchReason.SessionLogon
                Thread.Sleep(1000)
                PCMonitor.SendInfo(PCMonitor.GetString())
            Case SessionSwitchReason.SessionUnlock
                Thread.Sleep(1000)
                PCMonitor.SendInfo(PCMonitor.GetString())
            Case SessionSwitchReason.SessionLock
                Thread.Sleep(1000)
                PCMonitor.SendInfo(PCMonitor.GetString())
        End Select
    End Sub

    Private Sub SystemEvents_TimeChanged(sender As Object, e As EventArgs)
        EventLog.WriteEntry("PCMonitor.TimeChanged",
            "Time changed; it is now " & DateTime.Now.ToLongTimeString())
    End Sub

    Private Sub SystemEvents_UPCChanged(sender As Object, e As UserPreferenceChangedEventArgs)
        EventLog.WriteEntry("PCMonitor.UserPreferenceChanged", e.Category.ToString())
    End Sub
End Class

Partial Class HiddenForm

    Private components As IContainer = Nothing

    Protected Overrides Sub Dispose(disposing As Boolean)
        If disposing AndAlso Not (components Is Nothing) Then
            components.Dispose()
        End If
        MyBase.Dispose(disposing)
    End Sub

    Private Sub InitializeComponent()
        SuspendLayout()
        AutoScaleDimensions = New Drawing.SizeF(6.0F, 13.0F)
        AutoScaleMode = AutoScaleMode.Font
        ClientSize = New Drawing.Size(0, 0)
        FormBorderStyle = FormBorderStyle.None
        Name = "HiddenForm"
        Text = "HiddenForm"
        WindowState = FormWindowState.Minimized
        AddHandler Load, AddressOf HiddenForm_Load
        AddHandler FormClosing, AddressOf HiddenForm_FormClosing
        ResumeLayout(False)
    End Sub
End Class
<RunInstaller(False)>
Public Class SimpleInstaller
    Inherits Installer

    Private serviceInstaller As ServiceInstaller
    Private processInstaller As ServiceProcessInstaller

    Public Sub New()
        processInstaller = New ServiceProcessInstaller()
        serviceInstaller = New ServiceInstaller()

        ' Service will run under system account
        processInstaller.Account = ServiceAccount.LocalSystem

        ' Service will have Start Type of Manual
        serviceInstaller.StartType = ServiceStartMode.Automatic

        serviceInstaller.ServiceName = "PCMonitor"

        Installers.Add(serviceInstaller)
        Installers.Add(processInstaller)
    End Sub
End Class

Thanks

[techgnome]

I could be wrong about this, but Services run under a special service account... not the user ... so there's no context switching happening. I could be wrong though... probably am... But if not, that would make sense why it's not getting picked up.


-tg

[threeeye]

I could be wrong about this, but Services run under a special service account... not the user ... so there's no context switching happening. I could be wrong though... probably am... But if not, that would make sense why it's not getting picked up.


-tg

I read something about it, so I think you are not wrong...
Do you think there is a work around?