Change property structure at time of JSON serialization

Question

I have a situation where my HTML form represents a different data structure than the existing structure on the server.

To illustrate my problem, I will present a hypothetical situation, to present what solution I need:

My class:

public class Pessoa{
    public long Codigo {get;set;}
    public Estado Estado {get;set;}
}

[ModelBinder(typeof(EstadoBinder))] 
public class Estado{
    public static Estado ObtenhaEstado(long codigo){
       // Obtêm instância de estado a partir do código
    }

    public long Codigo {get;set;}
}

My HTML:

<div id='formularioPessoa'>
   <input type='text' name='Codigo' />
   <input type='text' name='Estado' />
</div>

As you can see in the HTML snippet, I need the 'State' input to reflect the Status object of my Person class.

For the interaction of CLIENT to SERVER, I already managed a solution implementing a custom Binder, implementing the Imodelbinder interface. The solution was excellent, as it did not require any class other than the state itself to know this particularity.

My need:

Now, I need something to handle SERVER to CLIENT interaction, when there is a serialization of a C# object to a JSON object.

What I need is that, when serializing any object that contains a state property, this serializer knows that I must send a JSON in this structure (below, the example of the Person serialization):

{
  "Codigo": "1",
  "Estado": "2"
}

Instead of:

{
  "Codigo": "1",
  "Estado": {
              Codigo: "2"
            }
}

I have researched a lot of material in English, including searching for something associated with Datetime, in relation to 'Custom serializers', 'Override Json method of controller', however, I did not find any elegant solution like the solution I found for the interaction Client > Server (Imodelbinder).

A caveat:

• I cannot use Html Helpers or other ASP.NET MVC code in my CSHTML file.

Answer 1

Theoretically you could do so in your controller

    public JsonResult Pessoas()
    {

        var pessoas = db.Pessoas.Select(s => new { Codigo = s.Codigo , Estado =  s.Estado.Codigo });

        return Json(pessoas , JsonRequestBehavior.AllowGet);
    }