using System.Text.Json;

using System;

using System.Collections.Generic;

​

namespace SerializeExtra

{

    public class Body

    {

      public List<User> users { get; set; }

    }

​

    public class User

    {

        public string Name { get; set; }

        public int Age { get; set; }

    }

​

    public class Program

    {

        public static void Main()

        {

          var users = new List<User>();

          users.Add(new User { Name = "Alice",Age = 20 });

          users.Add(new User { Name = "Bob",Age = 30 });

          var body = new Body

            {

                users = users,

            };

​

            var options = new JsonSerializerOptions { WriteIndented = true };

            string jsonString = JsonSerializer.Serialize(body, options);

​

            Console.WriteLine(jsonString);

        }

    }

}

​