[Bug Report] PnP APIs. TryGetValue fails with ACK properties

[rido-min]

Reported properties can use the ACK format (ac, av, ad, value).

I expected CloudProperty.TryGetValue knows about that format and tries to deserialize the value if present.

Repro code

using Microsoft.Azure.Devices.Client;
using Microsoft.Azure.Devices.Shared;
using System;
using System.Threading.Tasks;

namespace Rido.Samples
{
    
    class Program
    {
        static async Task Main(string[] args)
        {
            var mid = "dtmi:rido:simulator;1";
            var CS = Environment.GetEnvironmentVariable("CS");
            var dc = DeviceClient.CreateFromConnectionString(CS, TransportType.Mqtt, new ClientOptions { ModelId = mid });

            bool SendDataEnabled = true;

            //device reports the default value using the ack format
            IWritablePropertyResponse ack = dc.PayloadConvention.PayloadSerializer
                         .CreateWritablePropertyResponse(
                             SendDataEnabled, CommonClientResponseCodes.OK,1);

            var propertiesToBeUpdated = new ClientPropertyCollection();
            propertiesToBeUpdated.AddRootProperty("SendDataEnabled", ack);
            await dc.UpdateClientPropertiesAsync(propertiesToBeUpdated);

            var props = await dc.GetClientPropertiesAsync();
            // TryGetValue fails because the property is not bool
            if (props.TryGetValue<bool>("SendDataEnabled", out SendDataEnabled))
            {
                Console.WriteLine("Found reported SendDataEnabled: " + SendDataEnabled);
            } 
            else
            {
                Console.WriteLine("reported SendDataEnabled not found");
            }

            Console.WriteLine("Enter to Exit");
            Console.ReadLine();
        }
    }
}

[abhipsaMisra]

@rido-min I think there is a mismatch in the expectations of calling TryGetValue on a writable property.
(1) To retrieve the value of service requested writable property update - props.TryGetValue<bool>("SendDataEnabled", out SendDataEnabled)
(2) To retrieve the value of device reported writable property value - props.TryGetValue<NewtonsoftJsonWritablePropertyResponse>("SendDataEnabled", out SendDataEnabled)

For (2), the expectation is that you would get the complete writable property response that is associated with that property (value, ac, av, ad (if present)). You can call .Value on it to fetch the actual value.

This does necessitate the knowledge of NewtonsoftJsonWritablePropertyResponse though, so I agree that it isn't the most intuitive API.
I am going to link this issue to #2097, since they touch the same topic of making a writable property response more discoverable.

[abhipsaMisra]

We've now added support for TryGetValue with the following features:

For writable property update responses reported from the client, you should be able to retrieve the property as:

• generic IWritablePropertyResponse
• your implemented IWritablePropertyResponse
• the .Value part of the IWritablePropertyResponse

[abhipsaMisra]

This feature has now been released in https://github.com/Azure/azure-iot-sdk-csharp/releases/tag/preview_2021-10-8.