Public Class Service1
 
    Dim tmr As Timers.Timer
 
    Protected Overrides Sub OnStart(ByVal args() As String)
        tmr = New Timers.Timer()
        tmr.Interval = 100
 
        AddHandler tmr.Elapsed, AddressOf myTickHandler
        tmr.Enabled = True
        classWrite.writeLogFile("Service gestartet" + vbNewLine)
    End Sub
 
    Protected Overrides Sub OnStop()
        tmr.Enabled = False
        classWrite.writeLogFile("Service gestoppt" + vbNewLine)
    End Sub
 
    Private Sub myTickHandler(obj As Object, e As EventArgs)
        dim result as integer = [Datenbankabfrage]
        If result = 1 then
           MsgBox("blabla")
           tmr.Enabled = False           
        End if
    End Sub
 
End Class