Azure IoT Hub Framework 3.5

2 回答

• 1

  IoT Hub使设备能够直接使用MQTT v3.1.1协议与IoT Hub设备 endpoints 进行通信 . 你可以看一下这个document . 在文档中，教程是用python编写的，下面的代码是使用uPLibrary.Networking.M2Mqtt的C＃的完整示例 .

  C# Example:

  private static string hostName = "<iothub-hosename>";
      private static int port = 8883;
      private static string deviceId = "<deviceid>";
      private static string userName = "";
      private static string password = "";
      private static string certBase64 = "<DigiCert Baltimore Root Certificate>";
  
      static void Main(string[] args)
      {
  
          try
          {
              userName = $"{hostName}/{deviceId}/api-version=2016-11-14";
              password = $"SharedAccessSignature sr=<SAS Token>";
  
              byte[] certBytes = Convert.FromBase64String(certBase64);
              X509Certificate caCert = new X509Certificate(certBytes);
  
              MqttClient client = new MqttClient(hostName, port, true, caCert, null , MqttSslProtocols.TLSv1_0);
              client.ProtocolVersion = MqttProtocolVersion.Version_3_1_1;
  
              client.MqttMsgPublishReceived += Client_MqttMsgPublishReceived;
              client.MqttMsgPublished += Client_MqttMsgPublished;
              client.ConnectionClosed += Client_ConnectionClosed;
              client.Connect(deviceId, userName, password);
              if(client.IsConnected)
              {
                  //To receive messages from IoT Hub, a device should subscribe using devices/{device_id}/messages/devicebound/# as a Topic Filter. 
                  client.Subscribe(new string[] { $"devices/{deviceId}/messages/devicebound/#" }, new byte[] { MqttMsgBase.QOS_LEVEL_AT_LEAST_ONCE });
  
                  //After making a successful connection, a device can send messages to IoT Hub using devices/{device_id}/messages/events/ or devices/{device_id}/messages/events/{property_bag} as a Topic Name. 
                  client.Publish($"devices/{deviceid}/messages/events/", System.Text.Encoding.ASCII.GetBytes("{id=123}"), MqttMsgBase.QOS_LEVEL_AT_LEAST_ONCE, false);
              }
          }
          catch(Exception ex)
          {
              Console.Write(ex.Message);
          }
  
          Console.Read();
      }
  
      private static void Client_MqttMsgPublished(object sender, MqttMsgPublishedEventArgs e)
      {
          Console.WriteLine("Mqtt Published Message-[MsgId:{0}]:{1}", e.MessageId, e.IsPublished ? "Success": "Failure");
      }
  
      private static void Client_ConnectionClosed(object sender, EventArgs e)
      {
          Console.WriteLine("ConnectionClosed");
      }
  
      private static void Client_MqttMsgPublishReceived(object sender, MqttMsgPublishEventArgs e)
      {
          Console.WriteLine(System.Text.Encoding.ASCII.GetString(e.Message));
      }
  

  在代码中，您可能需要将 DigiCert Baltimore Root Certificate 从certs.c复制为 certBase64 作为base64字符串（删除行 -----BEGIN CERTIFICATE----- 和 -----END CERTIFICATE----- ，并删除 \r\n\ ） .

  Update:
  

  How to get SAS token?

  您可以使用Device Explorer生成SAS令牌，请参阅Using IoT Hub security tokens的设备部分 .

  回复于 2024-04-30T12:49:31+08:00
• 1

  你指的是 Azure IoT Hub device SDK for .NET ，它是否与 .NET Framework 3.5 一起使用？根据GitHub documentation，似乎IoT Hub SDK for .NET仅支持.NET Framework 4.5.1及更高版本 .

  或者，只需使用Azure IoT Hub Rest API - 然后您就可以从旧的.NET Framework 3.5代码发出HTTP请求

  回复于 2024-04-30T12:49:31+08:00