azure-iot-sdk - .NET 从 Microsoft.Azure.Devices.Client.ModuleClient 获取 DeviceId

所以我们必须使用后端解决方案来读取模块孪生属性，比如 deviceId。这是设计使然，您必须按照以下文档中的说明使用后端应用程序：模块双胞胎，在模块应用程序内部只有 Desired 和 Reported 可用。

示例控制台 C# 应用程序：利用“registryManager”使用查询语言查询所有设备。查询功能由RegistryManager 类中的C# 服务 SDK公开。

var query = registryManager.CreateQuery("SELECT * FROM devices", 100);

完整的示例控制台 C# 代码片段如下所示。[使用 Microsoft.Azure.Devices；]

using Microsoft.Azure.Devices;
using Microsoft.Azure.Devices.Common.Exceptions;
using Newtonsoft.Json;
using System;
using System.Threading.Tasks;

namespace CreateIds
{
    class Program
    {
        const string connectionString ="<>";     
        static void Main(string[] args)
        {
            GetDeviceIdAsync().Wait();
        }
        private static async Task GetDeviceIdAsync()
        {
            RegistryManager registryManager =
              RegistryManager.CreateFromConnectionString(connectionString);
            try
            {
                
                var query = registryManager.CreateQuery("SELECT * FROM devices", 100);
                while (query.HasMoreResults)
                {
                    var page = await query.GetNextAsTwinAsync();
                    foreach (var twin in page)
                    {
                        Console.WriteLine(JsonConvert.SerializeObject(twin.DeviceId));
                    }
                }
            }
            catch (DeviceAlreadyExistsException dvcEx)
            {
                Console.WriteLine("Error : {0}", dvcEx);
            }

        }
    }
}

更新 1：使用 'Where' 子句从devices.modules获取 deviceId 示例 json twin如下所示。现在我们必须使用像 moduleId='sampleModule' 这样的 'Where' 子句进行查询

Sample:{"deviceId":"devkitdps","moduleId":"sampleModule","etag":"AAAAAAAAAAE=","version":4,"status":"enabled","statusUpdateTime":"0001-01-01T00:00:00Z","connectionState":"Disconnected","lastActivityTime":"0001-01-01T00:00:00Z","cloudToDeviceMessageCount":0,"authenticationType":"sas","x509Thumbprint":{"primaryThumbprint":null,"secondaryThumbprint":null},"properties":{"desired":{"$metadata":{"$lastUpdated":"0001-01-01T00:00:00Z"},"$version":1},"reported":{"DateTimeLastAppLaunch":"2020-06-23T17:22:19.4938255-07:00","$metadata":{"$lastUpdated":"2020-06-24T00:22:19.6523448Z","DateTimeLastAppLaunch":{"$lastUpdated":"2020-06-24T00:22:19.6523448Z"}},"$version":3}}}

  var query = registryManager.CreateQuery("SELECT * FROM devices.modules Where moduleId='sampleModule'", 100);
                while (query.HasMoreResults)
                {
                    var page = await query.GetNextAsTwinAsync();
                    foreach (var twin in page)
                    {
                        Console.WriteLine(JsonConvert.SerializeObject(twin.DeviceId));
                    }
                }

如果您需要进一步的帮助，请告诉我们！

azure-iot-sdk - .NET 从 Microsoft.Azure.Devices.Client.ModuleClient 获取 DeviceId

问题描述

解决方案

推荐阅读