Question

I have a controller inherited from ControllerApi like this (MVC 4)

public HttpResponseMessage<lightUserInfo> Post(LogOnModel model)
{
    if (ModelState.IsValid)
    {
            if (Membership.ValidateUser(model.UserName, model.Password))
            {
                MembershipUser user = Membership.GetUser(model.UserName);
                var userinfo = new lightUserInfo(user);
                return new HttpResponseMessage<lightUserInfo>(userinfo);
            }
    }
 }

I can see the object userinfo is populated fine, and this returns 200 OK to the browser… but the Content is just empty json {}

Here is the client side ajax in CoffeeScript

$.ajax
  url: Meshable.rooturl + "/api/authentication"
  data:   JSON.stringify authenticationDetails    
  dataType: "json"
  type: "POST"
  contentType: 'application/json; charset=utf-8'
  error: (e) ->                     
  success: (data) ->
    #data comes in as empty {}

Answer 1

Do not assume that a POCO would be the simplest case and definitely serialize without any trouble. You have to mark it correctly. Include

using System.Runtime.Serialization;

Then mark the class like so

[DataContract]
public class UserInfo
{
    [DataMember]
    public string mystr {get; set;}

}