C# ตัวอย่าง top 100 ตัวอย่าง จากเว็บ csharphelper ครับ

namespace ConsoleApp3
{
    class Program
    {
        static void Main(string[] args)
        {
            ClientReceiveTest();            
        }

        public static void ClientReceiveTest()
        {
            var receivedMessage = false;
            // create the client
            //var client = new MQTTClient("test.mosquitto.org", 1883);
            var client = new MQTTClient("69.96.69.96", 1883);
                        
            // hook up the MessageReceived event with a handler
            client.MessageReceived += (topic, qos, payload) =>
            {
                Debug.WriteLine("RX: " + topic); //ห่าเหวอะไรก็ว่ากันไป
                //Write to RDBMS/Time Series Database
                receivedMessage = true;
            };
           
            var i = 0;
            // connect to the MQTT server
            client.Connect("หิวหอย6969", "UserName", "Password");
            // wait for the connection to complete
            while (!client.IsConnected)
            {
                Thread.Sleep(1000);

                if (i++ > 10)  break; 
            }

            // add a subscription
            client.Subscriptions.Add(new Subscription("wise/data"));
            
            i = 0;
            while (true)
            {
                if (receivedMessage)
                    break;

                Thread.Sleep(1000);

                // publish on our own subscribed topic to see if we hear what we send
                //client.Publish("Topic/Test/หิวหอย", "Hello World", QoS.FireAndForget, false);

                //if (i++ > 10) break;
            }
        }

    }
}

            client.MessageReceived += (topic, qos, payload) =>
            {
                Debug.WriteLine("RX: " + topic);
                receivedMessage = true;
            };

AddHandler client.MessageReceived , Sub(topic, qos, payload)
                                                                 Debug.WriteLine("RX" + topic)
                                                                 receivedMessage = True
                                                              End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
       'ass0 = sender As Object  (ใช้ sender ไม่ได้เพราะมันซ้ำ ต้องเปลี่ยนชื่อ แต่มันคือสิ่งเดียวกัน (คนละ Object)
       'ass1 = e As EventArgs (ใช้ sender ไม่ได้เพราะมันซ้ำ ต้องเปลี่ยนชื่อ แต่มันคือสิ่งเดียวกัน (คนละ Object)
        AddHandler btnSendData.Click, Sub(ass0 As Object, ass1 As EventArgs)
                                          MsgBox("Hi Hi Hi")
                                      End Sub
    End Sub