using System;

using Newtonsoft.Json;

using System.Collections.Generic;

​

public class Product

{

    public string Name

    {

        get;

        set;

    }

​

    public DateTime Expiry

    {

        get;

        set;

    }

​

    public string[] Sizes

    {

        get;

        set;

    }

}

​

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"};

        List<Product> productsArr = new List<Product>{

          product,

          product   

        };

        var dataObj = new

        {

        Data = productsArr

​

        ;

        string json = JsonConvert.SerializeObject(dataObj);

        Console.WriteLine(json);

    }

}