using System;

​

public class Program

{

    public static void Main()

    {

        var startDate = new DateTime(2019,05,28);

        // Do your operations

        var endDate   = new DateTime(2019, 05, 29);

        var ms = (endDate - startDate + new TimeSpan(8, 0, 0)).Milliseconds;

        Console.WriteLine(ms);

    }

}