using System;

using Newtonsoft.Json;

​

public class Program

{

    public static 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,

                            Newtonsoft.Json.Formatting.Indented, 

                            new JsonSerializerSettings { 

                                NullValueHandling = NullValueHandling.Ignore

                            });

        Console.WriteLine(json);

    }

}

​

public class Product

{

    public string Name

    {

        get;

        set;

    }

    public DateTime Expiry

    {

        get;

        set;

    }

    public string[] Sizes

    {

        get;

        set;

    }

}

​