How to Create a Simple Polling Service

Imports System.Threading

Public Class PollingService
    ' Keep track of worker thread.
    Private m_oPollingThread As New Thread( _
        New System.Threading.ThreadStart(AddressOf PollProcess))

    Protected Overrides Sub OnStart(ByVal args() As String)
        ' Add code here to start your service. This method should set things
        ' in motion so your service can do its work.
        EventLog1.WriteEntry("PollingService is starting.")

        ' Start the thread.
        m_oPollingThread.Start()
    End Sub

    Protected Overrides Sub OnStop()
        ' Add code here to perform any tear-down necessary to stop your service.
        EventLog1.WriteEntry("PollingService is stopping.")

        ' Stop the thread.
        m_oPollingThread.Abort()
    End Sub

    Private Sub PollProcess()
        ' Loops, until killed by OnStop.
        EventLog1.WriteEntry("PollingService service polling thread started.")
        Do
            ' Wait...
            System.Threading.Thread.Sleep(30000) ' 30000 = 30 seconds

            PollingPass()
        Loop
    End Sub

    Private Sub PollingPass()
        Try
            ' Do Stuff Here...
            EventLog1.WriteEntry("PollingService service polling pass executed.")
        Catch ex As System.Exception
            EventLog1.WriteEntry("PollingService encountered an error '" & _
                ex.Message & "'", EventLogEntryType.Error)
            EventLog1.WriteEntry("PollingService service Stack Trace: " & _
                ex.StackTrace, EventLogEntryType.Error)
        End Try
    End Sub

End Class