weekNumber property
int
weekNumber
Week number according to ISO 8601.
Implementation
int get weekNumber {
final thursday = DateTime.fromMillisecondsSinceEpoch(
((millisecondsSinceEpoch - 259200000) / 604800000).ceil() * 604800000,
);
final firstDayOfYear = DateTime(thursday.year, 1, 1);
return ((thursday.millisecondsSinceEpoch -
firstDayOfYear.millisecondsSinceEpoch) /
604800000)
.floor() +
1;
}