Question

我需要将此功能翻译成swift。基本上它是什么让它得到了＆＃39; n＆＃39;本周的一天。因此，例如，如果我将它与NSDate（）。getWeekDay（0）一起使用，它会给我9月21日，等等。但似乎在Swift-3中不再存在rangeOfUnit。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

有一个替代方案可以获得本周的开始直接翻译为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
    }
}

Answer 2

这是你在Swift 3中对Date的扩展和一点优化

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:)已在新dateInterval(of:start:interval:for:)结构中变为Calendar。

如何获得＆＃39; n＆＃39;工作日的约会

2 个答案: