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@yongjhih
Last active June 21, 2021 10:54
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extension DateTimeX<T extends DateTime> on T {
DateTime copyWith({
int year,
int month,
int day,
int hour,
int minute,
int second,
int millisecond,
int microsecond,
}) {
return DateTime(
year ?? this.year,
month ?? this.month,
day ?? this.day,
hour ?? this.hour,
minute ?? this.minute,
second ?? this.second,
millisecond ?? this.millisecond,
microsecond ?? this.microsecond,
);
}
/// Last day of this month
DateTime lastDay() => nextMonths().copyWith(day: 0);
DateTime lastDaySecond() => nextMonths().copyWith(
day: 1,
hour: 0,
minute: 0,
second: -1,
millisecond: 0,
microsecond: 0,
);
/// Last day moment of this month
///
/// Equivalent to first day moment of next month - 1 microsecond
DateTime lastDayMoment() => nextMonths().copyWith(
day: 1,
hour: 0,
minute: 0,
second: 0,
millisecond: 0,
microsecond: -1,
);
DateTime firstDay() => copyWith(day: 1);
/// First day moment of this month
DateTime firstDayMoment() => copyWith(
day: 1,
hour: 0,
minute: 0,
second: 0,
millisecond: 0,
microsecond: 0,
);
/// Last moment today
///
/// Equivalent to tomorrow first moment - 1 microsecond
DateTime lastMoment() => copyWith(
day: day + 1,
hour: 0,
minute: 0,
second: 0,
millisecond: 0,
microsecond: -1,
);
/// First moment today
DateTime firstMoment() => copyWith(
hour: 0,
minute: 0,
second: 0,
millisecond: 0,
microsecond: 0,
);
/// 1234567
/// ^
DateTime firstWeekday([int end]) => copyWith(
day: day - (DurationX.daysPerWeek) + 1,
);
DateTime firstWeekdayMoment([int end]) => copyWith(
day: day - (DurationX.daysPerWeek) + 1,
hour: 0,
minute: 0,
second: 0,
millisecond: 0,
microsecond: 0,
);
/// TODO end weekday
DateTime lastWeekday([int end]) => copyWith(
day: day + (DurationX.daysPerWeek) - 1,
);
/// TODO end weekday
DateTime lastWeekdayMoment([int end]) => copyWith(
day: day + (DurationX.daysPerWeek),
hour: 0,
minute: 0,
second: 0,
millisecond: 0,
microsecond: -1,
);
/// expect(3/31.monthAgo(), 2/29)
DateTime monthsAgo([int months = 1]) => copyWith(month: month - months).coerceAtMost(copyWith(month: month - months + 1, day: 0));
/// expect(1/31.nextMonth(), 2/29)
DateTime nextMonths([int months = 1]) => copyWith(month: month + months).coerceAtMost(copyWith(month: month + months + 1, day: 0));
DateTime yearsAgo([int years = 1]) => copyWith(year: year - years);
DateTime nextYears([int years = 1]) => copyWith(year: year + years);
DateTime weeksAgo([int weeks = 1]) => copyWith(day: day - (weeks * DurationX.daysPerWeek));
DateTime nextWeeks([int weeks = 1]) => copyWith(day: day + (weeks * DurationX.daysPerWeek));
DateTime yesterday() => daysAgo();
DateTime tomorrow() => nextDays();
DateTime daysAgo([int days = 1]) => copyWith(day: day - days);
DateTime nextDays([int days = 1]) => copyWith(day: day + days);
DateTimeRange hours({ bool inclusive = true }) => inclusive
? firstMoment().rangeTo(tomorrow().firstMoment(), step: 1.hours)
: firstMoment().rangeTo(lastMoment(), step: 1.hours);
/// 1234567
/// ^
DateTimeRange weekdays({ bool inclusive = true }) => inclusive
? firstMoment().rangeTo(nextWeeks().firstMoment(), step: 1.days)
: firstMoment().rangeTo(lastWeekdayMoment(), step: 1.days);
}
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