using System;

using System.Collections.Generic;

using Newtonsoft.Json;

using System.Linq;

public class Program

{

    public static void Main()

    {

        const string json = @"

            {

               'name':'Child1',

               'child':{

                  'item':{

                     'dict_item':{

                        'id':'car1',

                        'type':'car2'

                     }

                  }

               }

            }";

        var test = JsonConvert.DeserializeObject<Parent>(json);     

        Console.WriteLine(test.name);

        Console.WriteLine(test.child.item.First().Key);

        Console.WriteLine(test.child.item.First().Value.id);

        Console.WriteLine(test.child.item.First().Value.type);

    }

    public class Parent

    {

        public string name { get; set; }

        public Children child{ get; set; }

    }

​

    public class Children

    {

        public Dictionary<string, item> item{ get; set; }

    }

​

    public class item

    {

        public string id { get; set; }

        public string type { get; set; }

    }   

}