Public Sub Write(ByVal text As String)
        Dim txt As New StreamWriter("C:\Dummy.txt")
        txt.WriteLine(text)
        txt.Close()
    End Sub

Imports ServiceDLL
Public Class Service1
    Dim cl As New Class1()

    Protected Overrides Sub OnStart(ByVal args() As String)
        cl.Write("Service Started At : " + DateAndTime.Now)
    End Sub

    Protected Overrides Sub OnStop()
        cl.Write("Service Stoped At : " + DateAndTime.Now)
    End Sub
End Class