private static long GetAbsoluteDateUmAlQura(int year, int month, int day) { int yg = 0; int mg = 0; int dg = 0; UmAlQuraCalendar.ConvertHijriToGregorian(year, month, day, ref yg, ref mg, ref dg); return(GregorianCalendar.GetAbsoluteDate(yg, mg, dg)); }