assert(DateTime(Date(1999, 1, 6), TimeOfDay(0, 0, 0)).endOfMonth == DateTime(Date(1999, 1, 31), TimeOfDay(23, 59, 59))); assert(DateTime(Date(1999, 2, 7), TimeOfDay(19, 30, 0)).endOfMonth == DateTime(Date(1999, 2, 28), TimeOfDay(23, 59, 59))); assert(DateTime(Date(2000, 2, 7), TimeOfDay(5, 12, 27)).endOfMonth == DateTime(Date(2000, 2, 29), TimeOfDay(23, 59, 59))); assert(DateTime(Date(2000, 6, 4), TimeOfDay(12, 22, 9)).endOfMonth == DateTime(Date(2000, 6, 30), TimeOfDay(23, 59, 59)));
DateTime for the last day in the month that this DateTime is in. The time portion of endOfMonth is always 23:59:59.