using System;

using Newtonsoft.Json;

​

public class Program

{

    public class Product

    {

        public string Name {get; set;}

        public DateTime Expiry {get; set;}

        public string[] Sizes {get; set;}

    }

    public void Main()

    {

        Product product = new Product();

        product.Name = "Apple";

        product.Expiry = new DateTime(2008, 12, 28);

        product.Sizes = new string[] { "Small" };

        string json = JsonConvert.SerializeObject(product, Formatting.None);

        Console.WriteLine(json);

        json = JsonConvert.SerializeObject(product, Formatting.Indented);

        Console.WriteLine(json);

    }

}