如何能在IotEdge模块上计算从一个.NET应用程序的核心内触发？(How can computa

我需要触发从管理，后台应用程序的IotEdge模块上的一些计算。

在https://docs.microsoft.com/en-us/azure/iot-edge/module-development它说

目前，一个模块不能接收云对设备的消息

如此看来，直接调用方法似乎是要走的路。我如何能实现的直接方法，并从.NET核心应用内触发呢？

在你IotEdge模块的主要或init方法，你必须创建一个ModuleClient并将其连接到一个MethodHandler：

AmqpTransportSettings amqpSetting = new AmqpTransportSettings(TransportType.Amqp_Tcp_Only);
ITransportSettings[] settings = { amqpSetting };

ModuleClient ioTHubModuleClient = await ModuleClient.CreateFromEnvironmentAsync(settings);
await ioTHubModuleClient.OpenAsync();

await ioTHubModuleClient.SetMethodHandlerAsync("MyDirectMethodName", MyDirectMethodHandler, null);

然后，你必须在DirectMethodHandler添加到您的IotEge模块：

static async Task<MethodResponse> MyDirectMethodHandler(MethodRequest methodRequest, object userContext)
{
    Console.WriteLine($"My direct method has been called!");
    var payload = methodRequest.DataAsJson;
    Console.WriteLine($"Payload: {payload}");

    try
    {
        // perform your computation using the payload
    }
    catch (Exception e)
    {
         Console.WriteLine($"Computation failed! Error: {e.Message}");
         return new MethodResponse(Encoding.UTF8.GetBytes("{\"errormessage\": \"" + e.Message + "\"}"), 500);
    }

    Console.WriteLine($"Computation successfull.");
    return new MethodResponse(Encoding.UTF8.GetBytes("{\"status\": \"ok\"}"), 200);
}

从你的.NET应用程序的核心内你就可以触发这样的直接方法：

var iotHubConnectionString = "MyIotHubConnectionString";
var deviceId = "MyDeviceId";
var moduleId = "MyModuleId";
var methodName = "MyDirectMethodName";
var payload = "MyJsonPayloadString";

var cloudToDeviceMethod = new CloudToDeviceMethod(methodName, TimeSpan.FromSeconds(10));
cloudToDeviceMethod.SetPayloadJson(payload);

ServiceClient serviceClient = ServiceClient.CreateFromConnectionString(iotHubConnectionString);

try
{
    var methodResult = await serviceClient.InvokeDeviceMethodAsync(deviceId, moduleId, cloudToDeviceMethod);

    if(methodResult.Status == 200)
    {
        // Handle Success
    }
    else if (methodResult.Status == 500)
    {
        // Handle Failure
    }
 }
 catch (Exception e)
 {
     // Device does not exist or is offline
     Console.WriteLine(e.Message);
 }