How Do You “Really” Serialize Circular Referencing Objects With Newtonsoft.Json?

Question

I\'m having a problem getting some data serialized correctly from my ASP.NET Web API controller using Newtonsoft.Json.

Here\'s what I think is going on -

Answer 1

I wrote a minimal program to test this. Here is my github: https://github.com/assafwo1/TestSerializeJsonObjects. Here is the code:

using Newtonsoft.Json;
using System.Diagnostics;

namespace TestSerializeJsonObjects
{
    class Program
    {
        public class Node
        {
            public Node Next { get; set; }
        }
        static void Main(string[] args)
        {
            // create new node
            var head = new Node();
            // point its "next" field at itself
            head.Next = head;
            // this is now the smallest circular reference data structure possible 
            // assert that head next is head
            Debug.Assert(head.Next == head);
            // save to string
            var s = JsonConvert.SerializeObject(head, new JsonSerializerSettings
            {
                PreserveReferencesHandling = PreserveReferencesHandling.Objects
            });
            // get from string
            var head2 = JsonConvert.DeserializeObject(s, new JsonSerializerSettings
            {
                PreserveReferencesHandling = PreserveReferencesHandling.Objects
            });
            // assert that head2 next is head2
            Debug.Assert(head2.Next == head2);
            // done
        }
    }
}