Get Timestamp in ISO8601 format using c#

 private String GetFormattedTimestamp()
        {
            DateTime dateTime = DateTime.Now;
            return new DateTime(dateTime.Year, dateTime.Month, dateTime.Day,
                                 dateTime.Hour, dateTime.Minute, dateTime.Second,
                                 dateTime.Millisecond
                                , DateTimeKind.Local
                               ).ToUniversalTime().ToString("yyyy-MM-dd\\THH:mm:ss.fff\\Z",
                                CultureInfo.InvariantCulture);
        }