我正在使用这个扩展

 extension Double {

    func stringFromInterval() -> String {

        let timeInterval = Int(self)

        let millisecondsInt = Int((self.truncatingRemainder(dividingBy: 1)) * 1000)
        let secondsInt = timeInterval % 60
        let minutesInt = (timeInterval / 60) % 60
        let hoursInt = (timeInterval / 3600) % 24
        let daysInt = timeInterval / 86400

        let milliseconds = "\(millisecondsInt)ms"
        let seconds = "\(secondsInt)s" + " " + milliseconds
        let minutes = "\(minutesInt)m" + " " + seconds
        let hours = "\(hoursInt)h" + " " + minutes
        let days = "\(daysInt)d" + " " + hours

        if daysInt          > 0 { return days }
        if hoursInt         > 0 { return hours }
        if minutesInt       > 0 { return minutes }
        if secondsInt       > 0 { return seconds }
        if millisecondsInt  > 0 { return milliseconds }
        return ""
    }
}

用途不同

// assume myTimeInterval = 96460.397    
myTimeInteval.stringFromInterval() // 1d 2h 47m 40s 397ms

SWIFT 3.0方案基本基于上述方案，并进行了扩展。

extension CMTime {
  var durationText:String {
    let totalSeconds = CMTimeGetSeconds(self)
    let hours:Int = Int(totalSeconds.truncatingRemainder(dividingBy: 86400) / 3600)
    let minutes:Int = Int(totalSeconds.truncatingRemainder(dividingBy: 3600) / 60)
    let seconds:Int = Int(totalSeconds.truncatingRemainder(dividingBy: 60))

    if hours > 0 {
        return String(format: "%i:%02i:%02i", hours, minutes, seconds)
    } else {
        return String(format: "%02i:%02i", minutes, seconds)
    }

  }
}

用AVPlayer这样调用它?

 let dTotalSeconds = self.player.currentTime()
 playingCurrentTime = dTotalSeconds.durationText

我正在使用这个扩展

 extension Double {

    func stringFromInterval() -> String {

        let timeInterval = Int(self)

        let millisecondsInt = Int((self.truncatingRemainder(dividingBy: 1)) * 1000)
        let secondsInt = timeInterval % 60
        let minutesInt = (timeInterval / 60) % 60
        let hoursInt = (timeInterval / 3600) % 24
        let daysInt = timeInterval / 86400

        let milliseconds = "\(millisecondsInt)ms"
        let seconds = "\(secondsInt)s" + " " + milliseconds
        let minutes = "\(minutesInt)m" + " " + seconds
        let hours = "\(hoursInt)h" + " " + minutes
        let days = "\(daysInt)d" + " " + hours

        if daysInt          > 0 { return days }
        if hoursInt         > 0 { return hours }
        if minutesInt       > 0 { return minutes }
        if secondsInt       > 0 { return seconds }
        if millisecondsInt  > 0 { return milliseconds }
        return ""
    }
}

用途不同

// assume myTimeInterval = 96460.397    
myTimeInteval.stringFromInterval() // 1d 2h 47m 40s 397ms

以下是一个更结构化/灵活的方法:(Swift 3)

struct StopWatch {

    var totalSeconds: Int

    var years: Int {
        return totalSeconds / 31536000
    }

    var days: Int {
        return (totalSeconds % 31536000) / 86400
    }

    var hours: Int {
        return (totalSeconds % 86400) / 3600
    }

    var minutes: Int {
        return (totalSeconds % 3600) / 60
    }

    var seconds: Int {
        return totalSeconds % 60
    }

    //simplified to what OP wanted
    var hoursMinutesAndSeconds: (hours: Int, minutes: Int, seconds: Int) {
        return (hours, minutes, seconds)
    }
}

let watch = StopWatch(totalSeconds: 27005 + 31536000 + 86400)
print(watch.years) // Prints 1
print(watch.days) // Prints 1
print(watch.hours) // Prints 7
print(watch.minutes) // Prints 30
print(watch.seconds) // Prints 5
print(watch.hoursMinutesAndSeconds) // Prints (7, 30, 5)

使用这样的方法可以添加方便的解析，如下所示:

extension StopWatch {

    var simpleTimeString: String {
        let hoursText = timeText(from: hours)
        let minutesText = timeText(from: minutes)
        let secondsText = timeText(from: seconds)
        return "\(hoursText):\(minutesText):\(secondsText)"
    }

    private func timeText(from number: Int) -> String {
        return number < 10 ? "0\(number)" : "\(number)"
    }
}
print(watch.simpleTimeString) // Prints 07:30:05

值得注意的是，纯基于整数的方法不考虑闰日/秒。如果用例处理的是真实的日期/时间，则应该使用Date和Calendar。

NSTimeInterval是Double，使用扩展。例子:

extension Double {

    var formattedTime: String {

        var formattedTime = "0:00"

        if self > 0 {

            let hours = Int(self / 3600)
            let minutes = Int(truncatingRemainder(dividingBy: 3600) / 60)

            formattedTime = String(hours) + ":" + (minutes < 10 ? "0" + String(minutes) : String(minutes))
        }

        return formattedTime
    }
}

斯威夫特5:

extension Int {

    func secondsToTime() -> String {

        let (h,m,s) = (self / 3600, (self % 3600) / 60, (self % 3600) % 60)

        let h_string = h < 10 ? "0\(h)" : "\(h)"
        let m_string =  m < 10 ? "0\(m)" : "\(m)"
        let s_string =  s < 10 ? "0\(s)" : "\(s)"

        return "\(h_string):\(m_string):\(s_string)"
    }
}

用法:

let seconds : Int = 119
print(seconds.secondsToTime()) // Result = "00:01:59"