.NET之基于MQTTnet 实现MQTT服务器和客户端
前面说到MQTT技术介绍
现在物联网的概念很火，就工业智能互联来说，水平方向上如何把流水线式的孤岛式机台联动起来，我们比较有经验，但是垂直方向上，如何做数采，或者说如何高效灵活的做数采，需要补课的东西还有很多。MQTT是IBM很早以前就提出来的协议，但很可惜一直没有接触过，新公司的项目上引用了MQTTnet的开源库
官网指路：https://mqtt.org/
MQTTnet
MQTTnet是基于MQTT通信的高性能.NET库，它提供了一个MQTT客户端和一个MQTT服务器（代理）。支持.net core，支持MQTT 3.X和5.0版本。
https://github.com/chkr1011/MQTTnet
MQTTnet的Git路径。
正文
本Demo设计为一个WPF程序。基于MQTTnet，实现了一个MQTT Server或者说Broker的创建，同时在窗体上提供了MQTT Client的创建功能，MQTT Client跟Server连接之后，通过点击按钮，实现主题订阅、发布的基础功能。
并可以通过MQTTX工具调试。
MQTT Server/Broker实现
创建MQTT Server的思路还是蛮清晰的，主要是MqttServer各个事件的实现。
MQTT Server/Broker创建
先定义好MqttServerOptions，这是启动Mqtt服务时候的传参，定义服务启动时的各种参数：IP、Port口，账密等等
var optionsBuilder = new MqttServerOptionsBuilder();
实例化MqttServer以及委托实现MqttServer的各个事件
mqttServer = new MqttFactory().CreateMqttServer() as MqttServer; mqttServer.StartedHandler = new MqttServerStartedHandlerDelegate(OnMqttServerStarted); mqttServer.StoppedHandler = new MqttServerStoppedHandlerDelegate(OnMqttServerStopped);
下面是完成的实现代码：
public MqttServer mqttServer = null;
public async void StartMqttServer()
{
try
{
if (mqttServer == null)
{
var config = ReadConfiguration();
var optionsBuilder = new MqttServerOptionsBuilder()
.WithDefaultEndpoint().WithDefaultEndpointPort(int.Parse(config["Port"].ToString())).WithConnectionValidator(
c =>
{
var currentUser = config["Users"][0]["UserName"].ToString();
var currentPWD = config["Users"][0]["Password"].ToString();
if (currentUser == null || currentPWD == null)
{
c.ReasonCode = MqttConnectReasonCode.BadUserNameOrPassword;
return;
}
if (c.Username != currentUser)
{
c.ReasonCode = MqttConnectReasonCode.BadUserNameOrPassword;
return;
}
if (c.Password != currentPWD)
{
c.ReasonCode = MqttConnectReasonCode.BadUserNameOrPassword;
return;
}
c.ReasonCode = MqttConnectReasonCode.Success;
}).WithSubscriptionInterceptor(
c =>
{
c.AcceptSubscription = true;
}).WithApplicationMessageInterceptor(
c =>
{
c.AcceptPublish = true;
});
mqttServer = new MqttFactory().CreateMqttServer() as MqttServer;
mqttServer.StartedHandler = new MqttServerStartedHandlerDelegate(OnMqttServerStarted);
mqttServer.StoppedHandler = new MqttServerStoppedHandlerDelegate(OnMqttServerStopped);
mqttServer.ClientConnectedHandler = new MqttServerClientConnectedHandlerDelegate(OnMqttServerClientConnected);
mqttServer.ClientDisconnectedHandler = new MqttServerClientDisconnectedHandlerDelegate(OnMqttServerClientDisconnected);
mqttServer.ClientSubscribedTopicHandler = new MqttServerClientSubscribedHandlerDelegate(OnMqttServerClientSubscribedTopic);
mqttServer.ClientUnsubscribedTopicHandler = new MqttServerClientUnsubscribedTopicHandlerDelegate(OnMqttServerClientUnsubscribedTopic);
mqttServer.ApplicationMessageReceivedHandler = new MqttApplicationMessageReceivedHandlerDelegate(OnMqttServer_ApplicationMessageReceived);
await mqttServer.StartAsync(optionsBuilder.Build());
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, "MQTT Server is started."));
}
}
catch (Exception ex)
{
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Fatal, $"MQTT Server start fail.>{ex.Message}"));
}
}
public async void StopMqttServer()
{
if (mqttServer == null) return;
try
{
await mqttServer?.StopAsync();
mqttServer = null;
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, "MQTT Server is stopped."));
}
catch (Exception ex)
{
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Fatal, $"MQTT Server stop fail.>{ex.Message}"));
}
}
MQTT Server/Broker发布消息
从MQTT的设计来看，服务端是代理的角色，订阅者和发布者是客户端，所以通常来说，消息的订阅与发布应当都是客户端干的事。但是，服务端自然也是可以参与一下发布者的角色的。我还没想到这样用的实际场景，先功能实现一下——
很粗暴，先实例化一个MqttApplicationMessage对象，然后作为传参调用MqttServer.PublishAsync进行消息发布。
public async void ServerPublishMqttTopic(string topic, string payload)
{
var message = new MqttApplicationMessage()
{
Topic = topic,
Payload = Encoding.UTF8.GetBytes(payload)
};
await mqttServer.PublishAsync(message);
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, string.Format("MQTT Broker发布主题[{0}]成功！", topic)));
}
当然啦，MqttApplicationMessage还有很多属性值可以传，QoS(MqttQualityOfServiceLevel)、Retain等等，这里只是为了先实现功能，就只传了最简单的Topic和Payload。
MQTT Client创建
整体的实现思路跟Server端如出一辙，声明一个MqttClientOptions，赋值各种连接Server端需要的参数，最后作为MqttClient.ConnectAsync的传参，连接Server。
这里我在MqttClientOptions里面尝试了一下WillMessage，其实就是一个MqttApplicationMessage对象，WillMessage作为遗言机制，用于Client跟Server端挂点时的广播通知。
再之后就是实现MqttClient的各个事件，用来客制Connected，Disconnected，MessageReceived的各种逻辑，跟Server端实现没有什么区别，不再赘述。
private MqttClient mqttClient = null;
private async Task ClientStart()
{
try
{
var tcpServer = txtIPAddr.Text;
var tcpPort = int.Parse(txtPort.Text.Trim());
var mqttUser = txtUserName.Text.Trim();
var mqttPassword = txtPWD.Text.Trim();
var mqttFactory = new MqttFactory();
var options = new MqttClientOptions
{
ClientId = txtClientID.Text.Trim(),
ProtocolVersion = MQTTnet.Formatter.MqttProtocolVersion.V311,
ChannelOptions = new MqttClientTcpOptions
{
Server = tcpServer,
Port = tcpPort
},
WillDelayInterval = 10,
WillMessage = new MqttApplicationMessage()
{
Topic = $"LastWill/{txtClientID.Text.Trim()}",
Payload= Encoding.UTF8.GetBytes("I Lost the connection!"),
QualityOfServiceLevel = 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);
mqttClient = mqttFactory.CreateMqttClient() as MqttClient;
mqttClient.ConnectedHandler = new MqttClientConnectedHandlerDelegate(OnMqttClientConnected);
mqttClient.DisconnectedHandler = new MqttClientDisconnectedHandlerDelegate(OnMqttClientDisConnected);
mqttClient.ApplicationMessageReceivedHandler = new MqttApplicationMessageReceivedHandlerDelegate(OnSubscriberMessageReceived);
await mqttClient.ConnectAsync(options);
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, $"客户端[{options.ClientId}]尝试连接..."));
}
catch (Exception ex)
{
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Fatal, $"客户端尝试连接出错.>{ex.Message}"));
}
}
private async Task ClientStop()
{
try
{
if (mqttClient == null) return;
await mqttClient.DisconnectAsync();
mqttClient = null;
}
catch (Exception ex)
{
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Fatal, $"客户端尝试断开Server出错.>{ex.Message}"));
}
}
MQTT Client发布消息
这里的实现逻辑跟写法和Server端的发布别无二致，我在这里的MqttApplicationMessage补上了QoS和Retain的设置，由Form页面的控件传参。
这里补一句关于Retain的用法：Retain意为保留，设为True表示这条消息发布的时候如果没有订阅者，则该消息保留在Server端，直到被人订阅时立刻发布出去并删除，设为False时则没有这样的效果。
public async void ClientPublishMqttTopic(string topic, string payload)
{
try
{
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);
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, string.Format("客户端[{0}]发布主题[{1}]成功！", mqttClient.Options.ClientId, topic)));
}
catch (Exception ex)
{
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Fatal, string.Format("客户端[{0}]发布主题[{1}]异常！>{2}", mqttClient.Options.ClientId, topic,ex.Message)));
}
}
MQTT Clien订阅消息
呼叫MqttClient.SubscribeAsync，传入消息主题即可。
public async void ClientSubscribeTopic(string topic)
{
await mqttClient.SubscribeAsync(topic);
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, string.Format("客户端[{0}]订阅主题[{1}]成功！", mqttClient.Options.ClientId, topic)));
}
MQTT Clien取消订阅消息
呼叫MqttClient.UnsubscribeAsync，取消消息订阅。
public async void ClientUnSubscribeTopic(string topic)
{
await mqttClient.UnsubscribeAsync(topic);
lbxMonitor.BeginInvoke(_updateMonitorAction,
Logger.TraceLog(Logger.Level.Info, string.Format("客户端[{0}]取消主题[{1}]成功！", mqttClient.Options.ClientId, topic)));
}
以上代码是参考
总代码
服务端
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using MahApps.Metro.Controls;
using System.ComponentModel;
using MQTTnet.Server;
using MQTTnet.Adapter;
using MQTTnet.Protocol;
using MQTTnet;
using System.Collections.ObjectModel;
namespace MqttDemo.WPFServer
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : MetroWindow
{
private MainWindowModel _model;
private IMqttServer server;
public MainWindow()
{
InitializeComponent();
_model = new MainWindowModel();
this.DataContext = _model;
}
#region 启动按钮事件
private async void btnStart_Click(object sender, RoutedEventArgs e)
{
var optionBuilder = new MqttServerOptionsBuilder().WithDefaultEndpointBoundIPAddress(System.Net.IPAddress.Parse(_model.HostIP)).WithDefaultEndpointPort(_model.HostPort).WithDefaultCommunicationTimeout(TimeSpan.FromMilliseconds(_model.Timeout)).WithConnectionValidator(t =>
{
if (t.Username!=_model.UserName||t.Password!=_model.Password)
{
t.ReturnCode = MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
}
t.ReturnCode = MqttConnectReturnCode.ConnectionAccepted;
});
var option = optionBuilder.Build();
server = new MqttFactory().CreateMqttServer();
server.ApplicationMessageReceived += Server_ApplicationMessageReceived;//绑定消息接收事件
server.ClientConnected += Server_ClientConnected;//绑定客户端连接事件
server.ClientDisconnected += Server_ClientDisconnected;//绑定客户端断开事件
server.ClientSubscribedTopic += Server_ClientSubscribedTopic;//绑定客户端订阅主题事件
server.ClientUnsubscribedTopic += Server_ClientUnsubscribedTopic;//绑定客户端退订主题事件
server.Started += Server_Started;//绑定服务端启动事件
server.Stopped += Server_Stopped;//绑定服务端停止事件
//启动
await server.StartAsync(option);
}
#endregion
#region 停止按钮事件
private async void btnStop_Click(object sender, RoutedEventArgs e)
{
if (server != null)
{
await server.StopAsync();
}
}
#endregion
#region 服务端停止事件
private void Server_Stopped(object sender, EventArgs e)
{
WriteToStatus("服务端已停止！");
}
#endregion
#region 服务端启动事件
private void Server_Started(object sender, EventArgs e)
{
WriteToStatus("服务端已启动！");
}
#endregion
#region 客户端退订主题事件
private void Server_ClientUnsubscribedTopic(object sender, MqttClientUnsubscribedTopicEventArgs e)
{
this.Dispatcher.Invoke(() =>
{
if (_model.AllTopics.Any(t => t.Topic == e.TopicFilter))
{
TopicModel model = _model.AllTopics.First(t => t.Topic == e.TopicFilter);
_model.AllTopics.Remove(model);
model.Clients.Remove(e.ClientId);
model.Count--;
if (model.Count > 0)
{
_model.AllTopics.Add(model);
}
}
});
WriteToStatus("客户端" + e.ClientId + "退订主题" + e.TopicFilter);
}
#endregion
#region 客户端订阅主题事件
private void Server_ClientSubscribedTopic(object sender, MqttClientSubscribedTopicEventArgs e)
{
this.Dispatcher.Invoke(() =>
{
if (_model.AllTopics.Any(t => t.Topic == e.TopicFilter.Topic))
{
TopicModel model = _model.AllTopics.First(t => t.Topic == e.TopicFilter.Topic);
_model.AllTopics.Remove(model);
model.Clients.Add(e.ClientId);
model.Count++;
_model.AllTopics.Add(model);
}
else
{
TopicModel model = new TopicModel(e.TopicFilter.Topic, e.TopicFilter.QualityOfServiceLevel)
{
Clients = new List<string> { e.ClientId },
Count = 1
};
_model.AllTopics.Add(model);
}
});
WriteToStatus("客户端" + e.ClientId + "订阅主题" + e.TopicFilter.Topic);
}
#endregion
#region 客户端断开事件
private void Server_ClientDisconnected(object sender, MqttClientDisconnectedEventArgs e)
{
this.Dispatcher.Invoke(() =>
{
_model.AllClients.Remove(e.ClientId);
var query = _model.AllTopics.Where(t => t.Clients.Contains(e.ClientId));
if (query.Any())
{
var tmp = query.ToList();
foreach (var model in tmp)
{
_model.AllTopics.Remove(model);
model.Clients.Remove(e.ClientId);
model.Count--;
_model.AllTopics.Add(model);
}
}
});
WriteToStatus("客户端" + e.ClientId + "断开");
}
#endregion
#region 客户端连接事件
private void Server_ClientConnected(object sender, MqttClientConnectedEventArgs e)
{
this.Dispatcher.Invoke(() =>
{
_model.AllClients.Add(e.ClientId);
});
WriteToStatus("客户端" + e.ClientId + "连接");
}
#endregion
#region 收到消息事件
private void Server_ApplicationMessageReceived(object sender, MqttApplicationMessageReceivedEventArgs e)
{
if (e.ApplicationMessage.Topic == "/environ/temp")
{
string str = System.Text.Encoding.UTF8.GetString(e.ApplicationMessage.Payload);
double tmp;
bool isdouble = double.TryParse(str, out tmp);
if (isdouble)
{
string result = "";
if (tmp > 40)
{
result = "温度过高！";
}
else if (tmp < 10)
{
result = "温度过低！";
}
else
{
result = "温度正常！";
}
MqttApplicationMessage message = new MqttApplicationMessage()
{
Topic = e.ApplicationMessage.Topic,
Payload = Encoding.UTF8.GetBytes(result),
QualityOfServiceLevel = e.ApplicationMessage.QualityOfServiceLevel,
Retain = e.ApplicationMessage.Retain
};
server.PublishAsync(message);
}
}
WriteToStatus("收到消息" + e.ApplicationMessage.ConvertPayloadToString() + ",来自客户端" + e.ClientId + ",主题为" + e.ApplicationMessage.Topic);
}
#endregion
#region 打开配置页面
private void btnConfig_Click(object sender, RoutedEventArgs e)
{
this.flyConfig.IsOpen = !this.flyConfig.IsOpen;
}
#endregion
#region 增加主题按钮事件
private void btnAddTopic_Click(object sender, RoutedEventArgs e)
{
if (!string.IsNullOrWhiteSpace(_model.AddTopic)&&server!=null)
{
TopicModel topic = new TopicModel(_model.AddTopic, MqttQualityOfServiceLevel.AtLeastOnce);
foreach (string clientId in _model.AllClients)
{
server.SubscribeAsync(clientId, new List<TopicFilter> { topic });
}
_model.AllTopics.Add(topic);
}
}
#endregion
#region 清理内容
private void menuClear_Click(object sender, RoutedEventArgs e)
{
txtRich.Document.Blocks.Clear();
}
#endregion
#region 状态输出
/// <summary>
/// 状态输出
/// </summary>
/// <param name="message"></param>
public void WriteToStatus(string message)
{
if (!(txtRich.CheckAccess()))
{
this.Dispatcher.Invoke(() =>
WriteToStatus(message)
);
return;
}
string strTime = "[" + System.DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + "] ";
txtRich.AppendText(strTime + message + "\r");
}
#endregion
}
public class MainWindowModel : INotifyPropertyChanged
{
public MainWindowModel()
{
hostIP = "127.0.0.1";//绑定的IP地址
hostPort = 61613;//绑定的端口号12345
timeout = 3000;//连接超时时间
username = "admin";//用户名
password = "password";//密码
allTopics = new ObservableCollection<TopicModel>();//主题
allClients = new ObservableCollection<string>();//客户端
addTopic = "";
}
private ObservableCollection<TopicModel> allTopics;
public ObservableCollection<TopicModel> AllTopics
{
get { return allTopics; }
set
{
if (allTopics != value)
{
allTopics = value;
this.OnPropertyChanged("AllTopics");
}
}
}
private ObservableCollection<string> allClients;
public ObservableCollection<string> AllClients
{
get { return allClients; }
set
{
if (allClients != value)
{
allClients = value;
this.OnPropertyChanged("AllClients");
}
}
}
private string hostIP;
public string HostIP
{
get { return hostIP; }
set
{
if (hostIP != value)
{
hostIP = value;
this.OnPropertyChanged("HostIP");
}
}
}
private int hostPort;
public int HostPort
{
get { return hostPort; }
set
{
if (hostPort != value)
{
hostPort = value;
this.OnPropertyChanged("HostPort");
}
}
}
private int timeout;
public int Timeout
{
get { return timeout; }
set
{
if (timeout != value)
{
timeout = value;
this.OnPropertyChanged("Timeout");
}
}
}
private string username;
public string UserName
{
get { return username; }
set
{
if (username != value)
{
username = value;
this.OnPropertyChanged("UserName");
}
}
}
private string password;
public string Password
{
get { return password; }
set
{
if (password != value)
{
password = value;
this.OnPropertyChanged("Password");
}
}
}
private string addTopic;
public string AddTopic
{
get { return addTopic; }
set
{
if (addTopic != value)
{
addTopic = value;
this.OnPropertyChanged("AddTopic");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName = null)
{
var handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
public class TopicModel : TopicFilter,INotifyPropertyChanged
{
public TopicModel(string topic, MqttQualityOfServiceLevel qualityOfServiceLevel) : base(topic, qualityOfServiceLevel)
{
clients = new List<string>();
count = 0;
}
private int count;
/// <summary>
/// 订阅此主题的客户端数量
/// </summary>
public int Count
{
get { return count; }
set
{
if (count != value)
{
count = value;
this.OnPropertyChanged("Count");
}
}
}
private List<string> clients;
/// <summary>
/// 订阅此主题的客户端
/// </summary>
public List<string> Clients
{
get { return clients; }
set
{
if (clients != value)
{
clients = value;
this.OnPropertyChanged("Clients");
}
}
}
protected virtual void OnPropertyChanged(string propertyName = null)
{
var handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
public event PropertyChangedEventHandler PropertyChanged;
}
}
客户端：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using MahApps.Metro.Controls;
using MQTTnet;
using MQTTnet.Client;
using System.ComponentModel;
using MahApps.Metro.Controls.Dialogs;
namespace MqttDemo.MetroClient
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : MetroWindow
{
private MainWindowModel _model;
private IMqttClient _client;
public MainWindow()
{
InitializeComponent();
_model = new MainWindowModel()
{
AllTopics = InitTopics(),
SelectedTopics = new List<TopicFilter>(),
ServerUri = "127.0.0.1",
CurrentTopic = null,
ServerPort=61613,
ClientID = Guid.NewGuid().ToString("N")
};
this.DataContext = _model;
}
#region 订阅主题面板
/// <summary>
/// 打开订阅主题面板
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnSub_Click(object sender, RoutedEventArgs e)
{
this.flySub.IsOpen = !this.flySub.IsOpen;
}
#endregion
#region 用户配置面板
private void btnLogin_Click(object sender, RoutedEventArgs e)
{
this.flyLogin.IsOpen = !this.flyLogin.IsOpen;
}
#endregion
#region 数据初始化
/// <summary>
/// 数据初始化
/// </summary>
/// <returns></returns>
private List<TopicModel> InitTopics()
{
List<TopicModel> topics = new List<TopicModel>();
topics.Add(new TopicModel("/environ/temp", "环境-温度"));
topics.Add(new TopicModel("/environ/hum", "环境-湿度"));
//topics.Add(new TopicModel("/environ/pm25", "环境-PM2.5"));
//topics.Add(new TopicModel("/environ/CO2", "环境-二氧化碳"));
//topics.Add(new TopicModel("/energy/electric", "能耗-电"));
//topics.Add(new TopicModel("/energy/water", "环境-水"));
//topics.Add(new TopicModel("/energy/gas", "环境-电"));
topics.Add(new TopicModel("/data/alarm", "数据-报警"));
topics.Add(new TopicModel("/data/message", "数据-消息"));
topics.Add(new TopicModel("/data/notify", "数据-通知"));
return topics;
}
/// <summary>
/// 数据模型转换
/// </summary>
/// <param name="topics"></param>
/// <returns></returns>
private List<TopicFilter> ConvertTopics(List<TopicModel> topics)
{
//MQTTnet.TopicFilter
List<TopicFilter> filters = new List<TopicFilter>();
foreach (TopicModel model in topics)
{
TopicFilter filter = new TopicFilter(model.Topic,MQTTnet.Protocol.MqttQualityOfServiceLevel.AtLeastOnce);
filters.Add(filter);
}
return filters;
}
#endregion
#region 状态输出
/// <summary>
/// 状态输出
/// </summary>
/// <param name="message"></param>
public void WriteToStatus(string message)
{
if (!(txtRich.CheckAccess()))
{
this.Dispatcher.Invoke(() =>
WriteToStatus(message)
);
return;
}
string strTime = "[" + System.DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + "] ";
txtRich.AppendText(strTime + message + "\r");
if (txtRich.ExtentHeight > 200)
{
txtRich.Document.Blocks.Clear();
}
}
#endregion
#region 更改订阅的主题
/// <summary>
/// 保存订阅的主题
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnSave_Click(object sender, RoutedEventArgs e)
{
List<TopicModel> topics = _model.AllTopics.Where(t => t.IsSelected == true).ToList();
_model.SelectedTopics = ConvertTopics(topics);
this.flySub.IsOpen = !this.flySub.IsOpen;
SubscribeTopics(_model.SelectedTopics);
}
#endregion
#region 订阅主题
private void SubscribeTopics(List<TopicFilter> filters)
{
if (_client!=null)
{
_client.SubscribeAsync(filters);
string tmp = "";
foreach (var filter in filters)
{
tmp += filter.Topic;
tmp += ",";
}
if (tmp.Length>1)
{
tmp = tmp.Substring(0, tmp.Length - 1);
}
WriteToStatus("成功订阅主题："+tmp);
}
else
{
ShowDialog("提示", "请连接服务端后订阅主题！");
}
}
#endregion
#region 连接/断开服务端
/// <summary>
/// 连接服务端
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnStart_Click(object sender, RoutedEventArgs e)
{
if (_model.ServerUri!=null&&_model.ServerPort>0)
{
InitClient(_model.ClientID, _model.ServerUri, _model.ServerPort);
}
else
{
ShowDialog("提示", "服务端地址或端口号不能为空！");
}
}
/// <summary>
/// 断开服务端
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnStop_Click(object sender, RoutedEventArgs e)
{
if (_client != null)
{
_client.DisconnectAsync();
}
}
#endregion
#region MQTT方法
/// <summary>
/// 初始化
/// </summary>
/// <param name="id"></param>
/// <param name="url"></param>
/// <param name="port"></param>
private void InitClient(string id,string url = "127.0.0.1", int port = 1883)
{
var options = new MqttClientOptions()
{
ClientId = id
};
options.ChannelOptions = new MqttClientTcpOptions()
{
Server = url,
Port = port
};
options.Credentials = new MqttClientCredentials()
{
Username=_model.UserName,
Password=_model.Password
};
options.CleanSession = true;
options.KeepAlivePeriod = TimeSpan.FromSeconds(100);
options.KeepAliveSendInterval = TimeSpan.FromSeconds(10000);
if (_client != null)
{
_client.DisconnectAsync();
_client = null;
}
_client = new MQTTnet.MqttFactory().CreateMqttClient();
_client.ApplicationMessageReceived += _client_ApplicationMessageReceived;
_client.Connected += _client_Connected;
_client.Disconnected += _client_Disconnected;
_client.ConnectAsync(options);
}
/// <summary>
/// 客户端与服务端断开连接
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void _client_Disconnected(object sender, MqttClientDisconnectedEventArgs e)
{
_model.IsConnected = false;
_model.IsDisConnected = true;
WriteToStatus("与服务端断开连接！");
}
/// <summary>
/// 客户端与服务端建立连接
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void _client_Connected(object sender, MqttClientConnectedEventArgs e)
{
_model.IsConnected = true;
_model.IsDisConnected = false;
WriteToStatus("与服务端建立连接");
}
/// <summary>
/// 客户端收到消息
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void _client_ApplicationMessageReceived(object sender, MQTTnet.MqttApplicationMessageReceivedEventArgs e)
{
WriteToStatus("收到来自客户端" + e.ClientId + "，主题为" + e.ApplicationMessage.Topic + "的消息：" + Encoding.UTF8.GetString(e.ApplicationMessage.Payload));
}
#endregion
#region 发布消息
/// <summary>
/// 发布主题
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnPublish_Click(object sender, RoutedEventArgs e)
{
if (_client!=null)
{
if (this.comboTopics.SelectedIndex<0)
{
ShowDialog("提示", "请选择要发布的主题！");
return;
}
if (string.IsNullOrEmpty(txtContent.Text))
{
ShowDialog("提示", "消息内容不能为空！");
return;
}
string topic = comboTopics.SelectedValue as string;
string content = txtContent.Text;
MqttApplicationMessage msg = new MqttApplicationMessage
{
Topic=topic,
Payload=Encoding.UTF8.GetBytes(content),
QualityOfServiceLevel=MQTTnet.Protocol.MqttQualityOfServiceLevel.AtLeastOnce,
Retain=false
};
_client.PublishAsync(msg);
WriteToStatus("成功发布主题为" + topic+"的消息！");
}
else
{
ShowDialog("提示", "请连接服务端后发布消息！");
return;
}
}
#endregion
#region 提示框
public void ShowDialog(string title, string content)
{
_showDialog(title, content);
}
/// <summary>
/// 提示框
/// </summary>
/// <param name="title"></param>
/// <param name="content"></param>
private void _showDialog(string title, string content)
{
var mySetting = new MetroDialogSettings()
{
AffirmativeButtonText = "确定",
//NegativeButtonText = "Go away!",
//FirstAuxiliaryButtonText = "Cancel",
ColorScheme = this.MetroDialogOptions.ColorScheme
};
MessageDialogResult result = this.ShowModalMessageExternal(title, content, MessageDialogStyle.Affirmative, mySetting);
}
#endregion
private void btnSaveConfig_Click(object sender, RoutedEventArgs e)
{
}
}
public class MainWindowModel: INotifyPropertyChanged
{
private List<TopicModel> _allTopics;
public List<TopicModel> AllTopics
{
get { return _allTopics; }
set
{
if (_allTopics!=value)
{
_allTopics = value;
OnPropertyChanged("AllTopics");
}
}
}
private List<TopicFilter> _selectedTopics;
public List<TopicFilter> SelectedTopics
{
get { return _selectedTopics; }
set
{
if (_selectedTopics!=value)
{
_selectedTopics = value;
OnPropertyChanged("SelectedTopics");
}
}
}
private string _serverUri;
public string ServerUri
{
get { return _serverUri; }
set
{
if (_serverUri!=value)
{
_serverUri = value;
OnPropertyChanged("ServerUri");
}
}
}
private int _serverPort;
public int ServerPort
{
get { return _serverPort; }
set
{
if (_serverPort!=value)
{
_serverPort = value;
OnPropertyChanged("ServerPort");
}
}
}
private string _clientId;
public string ClientID
{
get { return _clientId; }
set
{
if (_clientId!=value)
{
_clientId = value;
OnPropertyChanged("ClientID");
}
}
}
private TopicFilter _currentTopic;
public TopicFilter CurrentTopic
{
get { return _currentTopic; }
set
{
if (_currentTopic!=value)
{
_currentTopic = value;
OnPropertyChanged("CurrentTopic");
}
}
}
private bool? _isConnected=false;
public bool? IsConnected
{
get { return _isConnected; }
set
{
if (_isConnected!=value)
{
_isConnected = value;
OnPropertyChanged("IsConnected");
}
}
}
private bool _isDisConnected=true;
public bool IsDisConnected
{
get { return _isDisConnected; }
set
{
if (_isDisConnected != value)
{
_isDisConnected = value;
this.OnPropertyChanged("IsDisConnected");
}
}
}
private string _userName="admin";
public string UserName
{
get { return _userName; }
set
{
if (_userName != value)
{
_userName = value;
this.OnPropertyChanged("UserName");
}
}
}
private string _password="password";
public string Password
{
get { return _password; }
set
{
if (_password != value)
{
_password = value;
this.OnPropertyChanged("Password");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName = null)
{
var handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
public class TopicModel: INotifyPropertyChanged
{
public TopicModel()
{
}
public TopicModel(string topic,string describe)
{
_isSelected = false;
_topic = topic;
_describe = describe;
}
private bool? _isSelected;
public bool? IsSelected
{
get { return _isSelected; }
set
{
if (_isSelected!=value)
{
_isSelected = value;
OnPropertyChanged("IsSelected");
}
}
}
private string _topic;
public string Topic
{
get { return _topic; }
set
{
if (_topic!=value)
{
_topic = value;
OnPropertyChanged("Topic");
}
}
}
private string _describe;
public string Describe
{
get { return _describe; }
set
{
if (_describe!=value)
{
_describe = value;
OnPropertyChanged("Describe");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged(string propertyName = null)
{
var handler = PropertyChanged;
if (handler != null) handler(this, new PropertyChangedEventArgs(propertyName));
}
}
}
源码：
https://github.com/ludewig/MqttDemo
鸣谢：
https://blog.csdn.net/xiakexingtx/article/details/108281359
https://blog.csdn.net/lordwish/article/details/84970800?spm=1001.2101.3001.6661.1&utm_medium=distribute.pc_relevant_t0.none-task-download-2%7Edefault%7ECTRLIST%7EPaid-1-13762029-blog-84970800.pc_relevant_paycolumn_v3&depth_1-utm_source=distribute.pc_relevant_t0.none-task-download-2%7Edefault%7ECTRLIST%7EPaid-1-13762029-blog-84970800.pc_relevant_paycolumn_v3&utm_relevant_index=1
本文来自博客园，作者：{春光牛牛,yak}，转载请注明原文链接：https://www.cnblogs.com/yakniu/p/16423899.html
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