NSdate

nsdate.md

                DateTime date = new DateTime(jsonObj.birth_year, jsonObj.birth_month, jsonObj.birth_day, 12, 0, 0);
                DateTime reference = new DateTime(2001, 1, 1, 0, 0, 0);
                NSDate dd = NSDate.FromTimeIntervalSinceReferenceDate(
                    (date - reference).TotalSeconds);
                event_date.DateValue = dd;

            DateTime d = DateTime.Parse(event_date.DateValue.ToString());