UWP應用，用於從Azure IoT中心接收消息

Question

我想制作UWP應用來接收來自Azure IoT中心的消息。 我找到了控制台接收器應用程序的示例代碼，但不適用於UWP，因為UWP不支持此引用。

using Microsoft.ServiceBus.Messaging;

有人可以為UWP應用發布代碼以從Azure IoT中心接收消息嗎？

Answer 1

我看過幾個帖子。 檢查這兩個：

• https://blogs.windows.com/buildingapps/2016/03/03/connect-your-windows-app-to-azure-iot-hub-with-visual-studio/
• https://azure.microsoft.com/en-us/documentation/samples/iot-hub-dotnet-uwp-remote-monitoring/

Answer 2

您可以嘗試使用AzureSBLite，也可以從NuGet程序包管理器中進行安裝。

https://github.com/ppatierno/azuresblite

接收的示例代碼：

string ConnectionString = "<EventHub-Compatible-EndPoint>;SharedAccessKeyName=iothubowner;SharedAccessKey<Key>
    static string eventHubEntity = "<EventHub-Compatible-Name>";
    string partitionId = "0";
    DateTime startingDateTimeUtc;
    EventHubConsumerGroup group;
    EventHubClient client;
    MessagingFactory factory;
    EventHubReceiver receiver;

public async Task ReceiveDataFromCloud()
    {
        startingDateTimeUtc = DateTime.UtcNow;
        ServiceBusConnectionStringBuilder builder = new ServiceBusConnectionStringBuilder(ConnectionString);
        builder.TransportType = ppatierno.AzureSBLite.Messaging.TransportType.Amqp;

        factory = MessagingFactory.CreateFromConnectionString(ConnectionString);

        client = factory.CreateEventHubClient(eventHubEntity);
        group = client.GetDefaultConsumerGroup();
        receiver = group.CreateReceiver(partitionId.ToString(), startingDateTimeUtc);//startingDateTimeUtc
        while (true)
        {
            EventData data = receiver.Receive();

            if (data != null)
            {
                var receiveddata = Encoding.UTF8.GetString(data.GetBytes());

                Debug.WriteLine("{0} {1} {2}", data.SequenceNumber, data.EnqueuedTimeUtc.ToLocalTime(), Encoding.UTF8.GetString(data.GetBytes()));

            }
            else
            {
                break;
            }

            await Task.Delay(2000);

        }

        receiver.Close();
        client.Close();
        factory.Close();

    }

您可以從IoTHub設置->消息傳遞部分獲取EventHub-Compatible-Endpoint和EventHub-Compatible Name。 在“設備到雲”設置下。

Answer 3

我也面臨着同樣的問題。我無法收到消息Azure IOT集線器。因為UWP不支持AMQP。 我已經嘗試過以下示例。但是我沒有運氣來接收消息。 https://github.com/Azure/azure-iot-sdks/tree/master/csharp/device/samples/UWPSample

如果您收到UWP中的消息，請告訴我。 計划在UWP中支持AMQP嗎？何時發布此更新？

Answer 4

官方SDK使用HTTP端點支持接收雲發送到設備的消息。 看到：

https://github.com/Azure/azure-iot-sdks/tree/master/csharp/device/samples/UWPSample

接收設備發送到雲的消息比較棘手，因為它是AMQP端點，但是可以使用AMQPNetLite完成：

https://paolopatierno.wordpress.com/2015/10/31/azure-iot-hub-commands-and-feedback-using-amqp-net-lite/

Answer 5

這是從物聯網接收消息的最佳方法。 有兩種方法可以實現此C2D和D2C ...雲到設備和設備到雲。 這取決於您的要求。 我對代碼進行了完整的測試：

public sealed partial class MainPage : Page
{
    public MainPage()
    {
        this.InitializeComponent();
        //txtblkMessages.Text = "test";
        Start();
    }

    private static int MESSAGE_COUNT = 1;

    private const string DeviceConnectionString = "HostName=[your hostname];DeviceId=[your DeviceId];SharedAccessKey=[your shared key]";
    public async Task Start()
    {
        try
        {
            DeviceClient deviceClient = DeviceClient.CreateFromConnectionString(DeviceConnectionString, TransportType.Amqp);
            //await SendEvent(deviceClient);
            await ReceiveCommands(deviceClient);
        }
        catch (Exception ex)
        {
            Debug.WriteLine("Error in sample: {0}", ex.Message);
        }
    }

    async Task SendEvent(DeviceClient deviceClient)
    {
        string dataBuffer;
        //for (int count = 0; count < MESSAGE_COUNT; count++)
        //{
        dataBuffer = "Hello Iot";
        Message eventMessage = new Message(Encoding.UTF8.GetBytes(dataBuffer));
        await deviceClient.SendEventAsync(eventMessage);
        // }
    }

    async Task ReceiveCommands(DeviceClient deviceClient)
    {
        Message receivedMessage;
        string messageData;
        while (true)
        {
            receivedMessage = await deviceClient.ReceiveAsync();
            if (receivedMessage != null)
            {
                messageData = Encoding.ASCII.GetString(receivedMessage.GetBytes());
                txtblkMessages.Text = messageData + "\n" + txtblkMessages.Text;
                await deviceClient.CompleteAsync(receivedMessage);
            }
            //  Note: In this sample, the polling interval is set to 
            //  10 seconds to enable you to see messages as they are sent.
            //  To enable an IoT solution to scale, you should extend this //  interval. For example, to scale to 1 million devices, set 
            //  the polling interval to 25 minutes.
            //  For further information, see
            //  https://azure.microsoft.com/documentation/articles/iot-hub-devguide/#messaging
            await Task.Delay(TimeSpan.FromSeconds(1));
        }
    }
}

Answer 6

請檢查我創建的UWP應用程序的源代碼：

https://github.com/Daniel-Krzyczkowski/WindowsIoTCore/blob/master/AzureTruckIoT/AzureTruckIoT.SensorsApp/Cloud/CloudDataService.cs

CloudDataService類包含兩種方法並使用IoT中心SDK：

• SendDataToTheCloud
• ReceiveDataFromTheCloud

這是一個如何使用UWP應用和IoT中心發送和接收消息的示例。