JsonConverter Attribute : deserialize using custom constructor and Autofac

Question

Am using a custom JsonConverter to convert my JSON object. This is achieved via the JsonConverter attribute to the IQuery object below

[JsonConverter(typeof(Cust         


        

Answer 1

Suppose an autofac setting like the following:

public class AutofacContractResolver : DefaultContractResolver
{
    private readonly IContainer _container;

    public AutofacContractResolver(IContainer container)
    {
        _container = container;
    }

    protected override JsonObjectContract CreateObjectContract(Type objectType)
    {
        JsonObjectContract contract = base.CreateObjectContract(objectType);

        // use Autofac to create types that have been registered with it
        if (_container.IsRegistered(objectType))
        {
           contract.DefaultCreator = () => _container.Resolve(objectType);
        }  

        return contract;
    }
}

Then, suppose your class is like this:

public class TaskController
{
    private readonly ITaskRepository _repository;
    private readonly ILogger _logger;

    public TaskController(ITaskRepository repository, ILogger logger)
    {
        _repository = repository;
        _logger = logger;
    }

    public ITaskRepository Repository
    {
        get { return _repository; }
    }

    public ILogger Logger
    {
        get { return _logger; }
    }
}

Therefore, the usage of the resolver in deserialization could be like:

ContainerBuilder builder = new ContainerBuilder();
builder.RegisterType().As();
builder.RegisterType();
builder.Register(c => new LogService(new DateTime(2000, 12, 12))).As();

IContainer container = builder.Build();

AutofacContractResolver contractResolver = new AutofacContractResolver(container);

string json = @"{
      'Logger': {
        'Level':'Debug'
      }
}";

// ITaskRespository and ILogger constructor parameters are injected by Autofac 
TaskController controller = JsonConvert.DeserializeObject(json, new JsonSerializerSettings
{
    ContractResolver = contractResolver
});

Console.WriteLine(controller.Repository.GetType().Name);

You can see more details in http://www.newtonsoft.com/json/help/html/DeserializeWithDependencyInjection.htm