using System;

using Newtonsoft.Json;

​

public class Program

{

    public static void Main()

    {

        var period = new OrderBlockPeriod

        {

            PeriodStart = DateTime.Now,

            PeriodEnd = DateTime.Now,

            Volume = 4.3m

        };

        Console.WriteLine(JsonConvert.SerializeObject(period));

    }

}

​

public class OrderBlockPeriod

{

    public DateTime PeriodStart { get; set; }

    public DateTime PeriodEnd { get; set; } 

    public decimal Volume { get; set; }

}

​