主题：[免费开源]狐表集成MQTT解决方案，MQTT是目前大热物联网领域最广泛使用的软硬件通讯协议。如果连MQTT都没听过，别说自己是做物联网项目的，会被人笑的....

(快速浏览杰哥分享过的所有经验汇总，点击跳转）

此主题相关图片如下：微信截图_20201210153205.png

此主题相关图片如下：1.png

 
此主题相关图片如下：2.png

Public MqttSub As mq.MqttClient 'MQTT的1个订阅端，方便连接后全局调用

Public MqttPub As mq.MqttClient 'MQTT的1个发布端，方便连接后全局调用

Public MqttQosDic As new Dictionary(of Integer,Byte)'qos质量枚举,在AfterOpenProject后初始化

'1订阅者相关---

'MQTT订阅者断开连接后触发的事件

Public Sub SubConnectionClosed(ByVal sender As Object, ByVal e As EventArgs)

    Functions.Execute("MqttSubDisConnected")

End Sub

'MQTT订阅者订阅后触发的事件

Public Sub MqttMsgSubscribed(ByVal sender As Object, ByVal e As mqs.MqttMsgSubscribedEventArgs)

    Functions.Execute("MqttMsgSubscribed")

End Sub

'MQTT订阅者收到消息时触发的事件

Public Sub MqttMsgPublishReceived(ByVal sender As Object, ByVal e As mqs.MqttMsgPublishEventArgs)

    Functions.Execute("MqttReceivedMessage",e.Message,e.Topic,e.QosLevel)

End Sub

'MQTT订阅者取消订阅后触发的事件

Public Sub MqttMsgUnsubscribed(ByVal sender As Object, ByVal e As mqs.MqttMsgUnsubscribedEventArgs)

    Functions.Execute("MqttMsgUnsubscribed")

End Sub

'2发布者相关

'MQTT发布者断开连接后触发的事件

Public Sub PubConnectionClosed(ByVal sender As Object, ByVal e As EventArgs)

    Functions.Execute("MqttPubDisConnected")

End Sub

'初始化MqttQos的枚举---

MqttQosDic.Add(0,mqs.MqttMsgBase.QOS_LEVEL_AT_MOST_ONCE) '0级,最多1次,消息可能会丢失

MqttQosDic.Add(1,mqs.MqttMsgBase.QOS_LEVEL_AT_LEAST_ONCE) '1级,最少1次,消息可能会重复

MqttQosDic.Add(2,mqs.MqttMsgBase.QOS_LEVEL_EXACTLY_ONCE) '2级,仅发1次,会增加开销甚至堵塞

'初始化MqttQos的枚举---

'MQTT订阅者订阅主题后触发的委托事件

'MQTT订阅者订阅后触发的委托事件

'订阅的MQTT收到信息时触发的事件

'注意编码有Default和UTF8,乱码请切换

Dim msg As String = Encoding.Default.GetString(args(0)) '消息内容

Dim Topic As String = args(1) '主题名

Dim QosLevel As Integer = args(2) 'qos质量，有0,1,2

'MQTT订阅者断开连接后触发的委托事件

'MQTT发布者断开连接后的委托事件

'对某个主题发送某个qos质量的消息

'通过 Functions.Execute("MqttPublish","主题","内容",0,False) 使用

'MqttQosDic是全局Qos枚举变量，已经定义好012级别

Dim Topic As String = Args(0) '主题

Dim msg As String = Args(1) '消息文本内容

Dim qos As Integer = Args(2) '质量等级，有012

Dim retain As Boolean = Args(3)

'Retain若为True，该条消息将被保留做为最后一条收到的消息。下一个订阅消息者将能至少收到该条消息

If MqttPub.IsConnected Then   

    '注意编码类型有Default和UTF8,乱码请切换

    MqttPub.Publish(Topic, Encoding.Default.GetBytes(msg), MqttQosDic(qos),retain)

End If

下载：

下载信息  [文件大小：   下载次数： ]

点击浏览该文件:help.zip

此主题相关图片如下：3.png

MqttSub = new mq.MqttClient("127.0.0.1",1884,False,new System.Security.Cryptography.X509Certificates.X509Certificate,new System.Security.Cryptography.X509Certificates.X509Certificate,new mq.MqttSslProtocols )

'或者new mq.MqttClient("http://域名:端口号/")

'把全局代码里自定义的事件委托给当前MqttSub实例

AddHandler MqttSub.ConnectionClosed, AddressOf SubConnectionClosed

AddHandler MqttSub.MqttMsgSubscribed, AddressOf MqttMsgSubscribed

AddHandler MqttSub.MqttMsgPublishReceived , AddressOf MqttMsgPublishReceived

AddHandler MqttSub.MqttMsgUnsubscribed, AddressOf MqttMsgUnsubscribed

If MqttSub.IsConnected =False Then

MqttSub.Connect(Guid.NewGuid.ToString,"admin","111") '指定连接的随机ID，账号，密码

'如果没有账号密码 MqttSub.Connect(Guid.NewGuid.ToString)

output.show(MqttSub.IsConnected)

End If

MqttSub.Subscribe({"mytopic"},{MqttQosDic(0)})

MqttSub.UnSubscribe({"mytopic"})

If MqttPub.IsConnected Then

    MqttPub.Disconnect

End If

MqttPub = new mq.MqttClient("127.0.0.1",1884,False,new System.Security.Cryptography.X509Certificates.X509Certificate,new System.Security.Cryptography.X509Certificates.X509Certificate,new mq.MqttSslProtocols )

'或者new mq.MqttClient("http://域名:端口号/")

'把全局代码里自定义的事件委托给当前MqttSub实例

AddHandler MqttPub.ConnectionClosed, AddressOf PubConnectionClosed

If MqttPub.IsConnected =False Then

    MqttPub.Connect(Guid.NewGuid.ToString,"admin","111") '指定连接的随机ID,账号,密码

    '如果没有账号密码 MqttSub.Connect(Guid.NewGuid.ToString)

    Output.show(MqttPub.IsConnected)

End If

Functions.Execute("MqttPublish","主题","内容",0,False)

If MqttPub.IsConnected Then

    MqttPub.Disconnect

End If