DateDiff.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

/*
 * 28/09/2015, Calculo de en milisegundos entre la fecha actual y 1970/01/01
 * Francisco Pérez, [email protected]
 */

namespace CSharpDateDiff
{
    class DateDiff
    {
        static void Main(string[] args)
        {
            long timestatmp = 1000 * (long) (DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds;

            Console.WriteLine(timestatmp);
        }
    }

}