isBetween method
Returns the bool wheather the given date are inside iterval or not.
Example:
DateTime(2000, 1, 2).isBetween(DateTime(2000, 1, 1), DateTime(2000, 1, 31)); // true
DateTime(2000, 1, 1).isBetween(DateTime(2000, 1, 1), DateTime(2000, 1, 1)); // true
Implementation
bool isBetween(DateTime from, DateTime to) {
return (isAfter(from) && isBefore(to)) || this == from || this == to;
}