ios - 如何获取日期的 'n' 工作日

Question

我需要将这个函数翻译成swift。基本上它得到了本周的“n”日是什么。因此，例如，如果我将它与 NSDate().getWeekDay(0) 一起使用，它会给我 9 月 11 日星期日，依此类推。但似乎 rangeOfUnit 不再存在于 Swift-3 中。这是我之前在 Swift-2 中的实现

extension NSDate {    func getWeekDay(day: Int) -> NSDate {        var beginningOfWeek: NSDate?        NSCalendar.currentCalendar().rangeOfUnit(NSCalendarUnit.WeekOfYear, startDate: &beginningOfWeek, interval: nil, forDate: self)        let comps = NSDateComponents()        comps.day = day        comps.minute = NSCalendar.currentCalendar().component(NSCalendarUnit.Minute, fromDate: self)        comps.hour = NSCalendar.currentCalendar().component(NSCalendarUnit.Hour, fromDate: self)        let nextDate = NSCalendar.currentCalendar().dateByAddingComponents(comps, toDate: beginningOfWeek!, options: .SearchBackwards)        return nextDate!    }}

Answer 1

有一个替代方法可以获取一周的开始时间直接转换为 Swift 3:

extension Date {
    func getWeekDay(day: Int) -> Date {
        let cal = Calendar.current
        let comps = cal.dateComponents([.weekOfYear, .yearForWeekOfYear], from: self)
        let beginningOfWeek = cal.date(from: comps)!
        let nextDate = cal.date(byAdding: .day, value: day, to: beginningOfWeek)!
        return nextDate
    }
}