如何获得日期的'n'工作日

Question

我需要将此函数转换为swift。 基本上它是什么得到本周的'n'天。因此，例如，如果我使用NSDate（）。getWeekDay（0），它会给我Sun 11月9日，依此类推。 但似乎rangeOfUnit不再存在于Swift-3中。 这是我以前在斯威夫特 - 2

 
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

实施有获得一周的开始，其 直接转化为斯威夫特3替代：

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 
    } 
} 

Answer 2

这是你在斯威夫特3个扩展为Date和位优化

extension Date { 
    func getWeekDay(day: Int) -> Date { 
    var beginningOfWeek = Date() 
    var interval : TimeInterval = 0 
    let currentCalendar = Calendar.current 
    currentCalendar.dateInterval(of: .weekOfYear, start: &beginningOfWeek, interval: &interval, for: self) 
    return currentCalendar.date(byAdding: .day, value: day, to: beginningOfWeek)! 
    } 
} 

rangeOfUnit(startDate:interval:forDate:)已经变成dateInterval(of:start:interval:for:)中的新Calendar结构。