Deserialize error object for RestSharp.Portable

JsonDeserializerOptional{TError}.cs

public class JsonDeserializerOptional<TError> : IDeserializer
{
    /// <summary>
    /// Deserialize the response
    /// </summary>
    /// <typeparam name="T">Object type to deserialize the result to</typeparam>
    /// <param name="response">The response to deserialize the result from</param>
    /// <returns>The deserialized object</returns>
    public T Deserialize<T>(IRestResponse response)
    {
        var input = new MemoryStream(response.RawBytes);
        using (var reader = new StreamReader(input))
        {
            var serializer = new JsonSerializer();
            ConfigureSerializer(serializer);

            var jsonReader = new JsonTextReader(reader);
            if (!response.IsSuccess)
            {
                TError errorData;
                try
                {
                    errorData = serializer.Deserialize<TError>(jsonReader);
                }
                catch
                {
                    throw new MyResponseException<TError>(response);
                }

                throw new MyResponseException<TError>(response, errorData);

            }

            return serializer.Deserialize<T>(jsonReader);
        }
    }

    /// <summary>
    /// Configure the JsonSerializer
    /// </summary>
    /// <param name="serializer">The serializer to configure</param>
    protected virtual void ConfigureSerializer(JsonSerializer serializer)
    {
    }
}

MyResponseException{TError}.cs

public class MyResponseException<TError> : Exception
{
    public MyResponseException(IRestResponse response, TError error) : base(response.StatusDescription)
    {
        Response = response;
        ErrorData = error;
    }

    public MyResponseException(IRestResponse response) : base(response.StatusDescription)
    {
        Response = response;
        ErrorData = default(TError);
    }

    public TError ErrorData { get; }

    public IRestResponse Response { get; }
}

TestClient.cs

// Init client once
var client = new RestClient(yourDestinationUrl)
{
    // Ignoring the status code is required, because otherwise the JSON deserializer
    // isn't run when the HTTP status code isn't 200.
    IgnoreResponseStatusCode = true
};

// Use our own JSON deserializer to be able to deserialize the error object
// and throw our own exception.
client.ClearHandlers();
client.AddHandler("application/json", new JsonDeserializerOptional<JsonErrorObject>());
client.AddHandler("text/json", new JsonDeserializerOptional<JsonErrorObject>());
client.AddHandler("text/x-json", new JsonDeserializerOptional<JsonErrorObject>());
client.AddHandler("text/javascript", new JsonDeserializerOptional<JsonErrorObject>());

// Call the API function

// Init request
var request = new RestRequest(subUrl);
// Execute request
try
{
    var responseData = (await client.Execute<JsonResponseObject>(request)).Data;
    // Work with the JsonResponseObject
}
catch (MyResponseException<JsonErrorObject> ex)
{
    // ex.ErrorData contains the JSON error object or null (e.g. due to an internal server error)
}