using MQTTnet.Client.Connecting; using MQTTnet.Client.Disconnecting; using MQTTnet.Client.Options; using MQTTnet.Client.Receiving; using MQTTnet.Protocol; using System.Text; using WinFormsMq.core; namespace WinFormsMq public partial class Form1 : Form private MqttClient mqttClient = null ; public Form1() InitializeComponent(); public void Init() cmbQos.SelectedIndex = 0 ; cmbRetain.SelectedIndex = 0 ; /// <summary> /// 连接服务器 /// </summary> private async Task ConnectMqttServerAsync() if (mqttClient == null ||! mqttClient.IsConnected) var mqttFactory = new MqttFactory(); mqttClient = mqttFactory.CreateMqttClient() as MqttClient; mqttClient.ConnectedHandler = new MqttClientConnectedHandlerDelegate(OnMqttClientConnected); mqttClient.DisconnectedHandler = new MqttClientDisconnectedHandlerDelegate(OnMqttClientDisConnected); mqttClient.ApplicationMessageReceivedHandler = new MqttApplicationMessageReceivedHandlerDelegate(OnSubscriberMessageReceived); var tcpServer = txtIPAddr.Text; // mqtt服务器地址 var tcpPort = int .Parse(txtPort.Text.Trim()); var mqttUser = txtUserName.Text.Trim(); var mqttPassword = txtPWD.Text.Trim(); var options = new MqttClientOptions ClientId = txtClientID.Text.Trim(), ProtocolVersion = MQTTnet.Formatter.MqttProtocolVersion.V311, ChannelOptions = new MqttClientTcpOptions Server = tcpServer, Port = tcpPort, WillDelayInterval = 100 , WillMessage = new MqttApplicationMessage() Topic = $ " LastWill/{txtClientID.Text.Trim()} " , Payload = Encoding.UTF8.GetBytes( " I lost the connection! " ), QualityOfServiceLevel = MQTTnet.Protocol.MqttQualityOfServiceLevel.ExactlyOnce if (options.ChannelOptions == null ) throw new InvalidOperationException(); if (! string .IsNullOrEmpty(mqttUser)) options.Credentials = new MqttClientCredentials Username = mqttUser, Password = Encoding.UTF8.GetBytes(mqttPassword) options.CleanSession = true ; options.KeepAlivePeriod = TimeSpan.FromSeconds( 5 ); await mqttClient.ConnectAsync(options); // 客户端尝试连接 catch (Exception ex) // 客户端尝试连接出错 this .Invoke( new Action(() => txtReceiveMessage.AppendText($ " MQTT服务器失败！ " + Environment.NewLine+ex.Message+ Environment.NewLine); public void OnMqttClientConnected(MqttClientConnectedEventArgs e) this .Invoke( new Action(() => txtReceiveMessage.AppendText( " 已连接到MQTT服务器！ " + Environment.NewLine); public void OnMqttClientDisConnected(MqttClientDisconnectedEventArgs e) this .Invoke( new Action(() => txtReceiveMessage.AppendText( " 客户机已断开！ " + Environment.NewLine); public void OnSubscriberMessageReceived(MqttApplicationMessageReceivedEventArgs e) this .Invoke( new Action(() => txtReceiveMessage.AppendText($ " >>{Encoding.UTF8.GetString(e.ApplicationMessage.Payload)}{Environment.NewLine} " ); /// <summary> /// 客户机断开 /// </summary> private async Task ClientStop() if (mqttClient != null ) await mqttClient.DisconnectAsync(); mqttClient = null ; return ; } catch (Exception ex) // 客户端尝试断开server出错 /// <summary> /// 发布消息 /// </summary> public async void ClientPublishMqttTopic( string topic, string payload) var message = new MqttApplicationMessage() Topic = topic, Payload = Encoding.UTF8.GetBytes(payload), QualityOfServiceLevel = (MqttQualityOfServiceLevel)cmbQos.SelectedIndex, Retain = bool .Parse(cmbRetain.SelectedItem.ToString()), await mqttClient.PublishAsync(message); // 客户端发送成工 mqttClient.Options.ClientId topic } catch (Exception ex) // 客户端发送异常 this .Invoke( new Action(() => txtReceiveMessage.AppendText(Logger.TraceLog(Logger.LogLevel.Info, String.Format($ " 发布消息失败{{1}}！{Environment.NewLine} " , ex.Message))); /// <summary> /// 传入消息主题 订阅消息 /// </summary> /// <param name="topic"></param> public async void ClientSubscribeTopic( string topic) await mqttClient.SubscribeAsync(topic); // 订阅成功 this .Invoke( new Action(() => txtReceiveMessage.AppendText(Logger.TraceLog(Logger.LogLevel.Info,String.Format($ " 客户端{{0}}订阅主题{{1}}成功！{Environment.NewLine} " , mqttClient.Options.ClientId,topic))); public async void ClientUnsubscribeTopic( string topic) await mqttClient.UnsubscribeAsync(topic); // 取消订阅 // 订阅成功 this .Invoke( new Action(() => txtReceiveMessage.AppendText(Logger.TraceLog(Logger.LogLevel.Info, String.Format($ " 客户端{{0}}取消订阅主题{{1}}成功！{Environment.NewLine} " , mqttClient.Options.ClientId, topic))); private void butCon_Click( object sender, EventArgs e) Task.Run( async () => { await ConnectMqttServerAsync(); }); private void Form1_Load( object sender, EventArgs e) Init(); /// <summary> /// 订阅 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void BtnSubscribe_Click( object sender, EventArgs e) string topic= txtSubTopic.Text.Trim(); if ( string .IsNullOrEmpty(topic)) MessageBox.Show( " 订阅主题不能为空! " ); return ; else if (! mqttClient.IsConnected) MessageBox.Show( " MQTT客户端尚未连接 " ); return ; ClientSubscribeTopic(topic); private void BtnPublish_Click( object sender, EventArgs e) string pubtopic= txtPubTopic.Text.Trim(); if ( string .IsNullOrEmpty(pubtopic)) MessageBox.Show( " 发布主题不能为空！ " ); return ; string inputString = txtSendMessage.Text.Trim(); ClientPublishMqttTopic(pubtopic, inputString); private void BtnUnSub_Click( object sender, EventArgs e) string topic = txtSubTopic.Text.Trim(); if ( string .IsNullOrEmpty(topic)) MessageBox.Show( " 取消订阅主题不能为空! " ); return ; if (! mqttClient.IsConnected) MessageBox.Show( " MQTT客户端尚未连接 " ); return ; ClientUnsubscribeTopic(topic); private void butUnCon_Click( object sender, EventArgs e) ClientStop();