周数 (ISO)

根据 周数 获取当年的周数。

¥Gets the number of weeks in the current year, according to ISO weeks.

This requires the IsoWeeksInYear plugin to work

dayjs.extend(isoWeeksInYear)
dayjs.extend(isLeapYear)

dayjs('2004-01-01').isoWeeksInYear() // 53
dayjs('2005-01-01').isoWeeksInYear() // 52