public void CheckListenerStates() { HttpListenerService listener = new HttpListenerService("http://localhost:8080/"); try { Assert.IsFalse(listener.isListening); listener.RunServer(); Assert.IsTrue(listener.isListening); listener.RunServer(); } catch (InvalidOperationException e) { Assert.AreEqual(e.Message, "Server is already running."); } finally { listener.StopServer(); Assert.IsFalse(listener.isListening); } }