title | description | author | manager | ms.service | services | ms.devlang | ms.topic | ms.custom | ms.date | ms.author |
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Send telemetry to Azure IoT Hub quickstart (C#) | Microsoft Docs |
In this quickstart, you run two sample C# applications to send simulated telemetry to an IoT hub and to read telemetry from the IoT hub for processing in the cloud. |
dominicbetts |
timlt |
iot-hub |
iot-hub |
csharp |
quickstart |
mvc |
06/20/2018 |
dobett |
Quickstart: Send telemetry from a device to an IoT hub and read the telemetry from the hub with a back-end application (C#)
[!INCLUDE iot-hub-quickstarts-1-selector]
IoT Hub is an Azure service that enables you to ingest high volumes of telemetry from your IoT devices into the cloud for storage or processing. In this quickstart, you send telemetry from a simulated device application, through IoT Hub, to a back-end application for processing.
The quickstart uses two pre-written C# applications, one to send the telemetry and one to read the telemetry from the hub. Before you run these two applications, you create an IoT hub and register a device with the hub.
[!INCLUDE cloud-shell-try-it.md]
If you don’t have an Azure subscription, create a free account before you begin.
The two sample applications you run in this quickstart are written using C#. You need the .NET Core SDK 2.1.0 or greater on your development machine.
You can download the .NET Core SDK for multiple platforms from .NET.
You can verify the current version of C# on your development machine using the following command:
dotnet --version
Download the sample C# project from https://github.com/Azure-Samples/azure-iot-samples-csharp/archive/master.zip and extract the ZIP archive.
[!INCLUDE iot-hub-include-create-hub]
A device must be registered with your IoT hub before it can connect. In this quickstart, you use the Azure Cloud Shell to register a simulated device.
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Run the following commands in Azure Cloud Shell to add the IoT Hub CLI extension and to create the device identity.
YourIoTHubName : Replace this placeholder below with the name you choose for your IoT hub.
MyDotnetDevice : This is the name given for the registered device. Use MyDotnetDevice as shown. If you choose a different name for your device, you will also need to use that name throughout this article, and update the device name in the sample applications before you run them.
az extension add --name azure-cli-iot-ext az iot hub device-identity create --hub-name YourIoTHubName --device-id MyDotnetDevice
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Run the following commands in Azure Cloud Shell to get the device connection string for the device you just registered:
YourIoTHubName : Replace this placeholder below with the name you choose for your IoT hub.
az iot hub device-identity show-connection-string --hub-name YourIoTHubName --device-id MyDotnetDevice --output table
Make a note of the device connection string, which looks like:
HostName={YourIoTHubName}.azure-devices.net;DeviceId=MyNodeDevice;SharedAccessKey={YourSharedAccessKey}
You use this value later in the quickstart.
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You also need the Event Hubs-compatible endpoint, Event Hubs-compatible path, and iothubowner primary key from your IoT hub to enable the back-end application to connect to your IoT hub and retrieve the messages. The following commands retrieve these values for your IoT hub:
YourIoTHubName : Replace this placeholder below with the name you choose for your IoT hub.
az iot hub show --query properties.eventHubEndpoints.events.endpoint --name YourIoTHubName az iot hub show --query properties.eventHubEndpoints.events.path --name YourIoTHubName az iot hub policy show --name iothubowner --query primaryKey --hub-name YourIoTHubName
Make a note of these three values, which you use later in the quickstart.
The simulated device application connects to a device-specific endpoint on your IoT hub and sends simulated temperature and humidity telemetry.
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In a local terminal window, navigate to the root folder of the sample C# project. Then navigate to the iot-hub\Quickstarts\simulated-device folder.
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Open the SimulatedDevice.cs file in a text editor of your choice.
Replace the value of the
s_connectionString
variable with the device connection string you made a note of previously. Then save your changes to SimulatedDevice.cs file. -
In the local terminal window, run the following commands to install the required packages for simulated device application:
dotnet restore
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In the local terminal window, run the following command to build and run the simulated device application:
dotnet run
The following screenshot shows the output as the simulated device application sends telemetry to your IoT hub:
The back-end application connects to the service-side Events endpoint on your IoT Hub. The application receives the device-to-cloud messages sent from your simulated device. An IoT Hub back-end application typically runs in the cloud to receive and process device-to-cloud messages.
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In another local terminal window, navigate to the root folder of the sample C# project. Then navigate to the iot-hub\Quickstarts\read-d2c-messages folder.
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Open the ReadDeviceToCloudMessages.cs file in a text editor of your choice. Update the following variables and save your changes to the file.
Variable Value s_eventHubsCompatibleEndpoint
Replace the value of the variable with the Event Hubs-compatible endpoint you made a note of previously. s_eventHubsCompatiblePath
Replace the value of the variable with the Event Hubs-compatible path you made a note of previously. s_iotHubSasKey
Replace the value of the variable with the iothubowner primary key you made a note of previously. -
In the local terminal window, run the following commands to install the required libraries for the back-end application:
dotnet restore
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In the local terminal window, run the following commands to build and run the back-end application:
dotnet run
The following screenshot shows the output as the back-end application receives telemetry sent by the simulated device to the hub:
[!INCLUDE iot-hub-quickstarts-clean-up-resources]
In this quickstart, you've setup an IoT hub, registered a device, sent simulated telemetry to the hub using a C# application, and read the telemetry from the hub using a simple back-end application.
To learn how to control your simulated device from a back-end application, continue to the next quickstart.
[!div class="nextstepaction"] Quickstart: Control a device connected to an IoT hub