using Newtonsoft.Json;

using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

        public class ObjectAttributeValue

    {

        public string value { get; set; }

    }

​

    public class Attribute

    {

        public int objectTypeAttributeId { get; set; }

        public List<ObjectAttributeValue> objectAttributeValues { get; set; }

    }

​

    public class RootObject

    {

        public int objectTypeId { get; set; }

        public List<Attribute> attributes { get; set; }

    }

    public static void Main()

    {

        RootObject controllerjson = new RootObject()

            {

                objectTypeId = 545,

                attributes = new List<Attribute>() {

                    new Attribute() {

                        objectTypeAttributeId = 222,

                        objectAttributeValues = new List<ObjectAttributeValue>() {

                            new ObjectAttributeValue() { value= "Kommentar" }

                        }

                    }

                }

            };

​

        string jsonStr = JsonConvert.SerializeObject(controllerjson);

        Console.WriteLine(jsonStr);

    }

}