string sUser = "Username1";

        MQTTClient client = new MQTTClient("test.mosquitto.org", 1883);
        client.Connect(sUser);
        client.Subscriptions.Add("TEST", QoS.FireAndForget);
        client.Subscriptions.Add("REMOVE", QoS.FireAndForget);
        client.Disconnected += (x,y) => {
            Console.Write("**Disconnected**");
            Console.ReadLine();
        };

        Console.WriteLine("Press any key to Publish to 'test'");
        Console.ReadLine();
        client.Publish("TEST", "Hello World", QoS.FireAndForget, false);

        Console.WriteLine("Press any key to Remove the topic 'remove'");
        Console.ReadLine();
        client.Subscriptions.Remove("REMOVE");

        Console.WriteLine("Press any key to Publish to 'test' again");
        Console.ReadLine();
        client.Publish("TEST", "Hello World Again", QoS.FireAndForget, false);

        Console.ReadLine();

    }`