另一种方法是将秒转换为日期，并从日期本身取秒、分和小时。 此解决方案仅限于23:59:59

我已经构建了一个现有答案的mashup，以简化一切并减少Swift 3所需的代码量。

func hmsFrom(seconds: Int, completion: @escaping (_ hours: Int, _ minutes: Int, _ seconds: Int)->()) {

        completion(seconds / 3600, (seconds % 3600) / 60, (seconds % 3600) % 60)

}

func getStringFrom(seconds: Int) -> String {

    return seconds < 10 ? "0\(seconds)" : "\(seconds)"
}

用法:

var seconds: Int = 100

hmsFrom(seconds: seconds) { hours, minutes, seconds in

    let hours = getStringFrom(seconds: hours)
    let minutes = getStringFrom(seconds: minutes)
    let seconds = getStringFrom(seconds: seconds)

    print("\(hours):\(minutes):\(seconds)")                
}

打印:

00:01:40

下面是Swift3中的另一个简单实现。

func seconds2Timestamp(intSeconds:Int)->String {
   let mins:Int = intSeconds/60
   let hours:Int = mins/60
   let secs:Int = intSeconds%60

   let strTimestamp:String = ((hours<10) ? "0" : "") + String(hours) + ":" + ((mins<10) ? "0" : "") + String(mins) + ":" + ((secs<10) ? "0" : "") + String(secs)
   return strTimestamp
}

恕我直言，最简单的方法是:

let hours = time / 3600
let minutes = (time / 60) % 60
let seconds = time % 60
return String(format: "%0.2d:%0.2d:%0.2d", hours, minutes, seconds)

@r3dm4n的回答很棒。然而，我也需要一个小时。以防别人也需要，这里是:

func formatSecondsToString(_ seconds: TimeInterval) -> String {
    if seconds.isNaN {
        return "00:00:00"
    }
    let sec = Int(seconds.truncatingRemainder(dividingBy: 60))
    let min = Int(seconds.truncatingRemainder(dividingBy: 3600) / 60)
    let hour = Int(seconds / 3600)
    return String(format: "%02d:%02d:%02d", hour, min, sec)
}

以下是我在Swift 4+中使用的音乐播放器。我将秒Int转换为可读的字符串格式

extension Int {
    var toAudioString: String {
        let h = self / 3600
        let m = (self % 3600) / 60
        let s = (self % 3600) % 60
        return h > 0 ? String(format: "%1d:%02d:%02d", h, m, s) : String(format: "%1d:%02d", m, s)
    }
}

像这样使用:

print(7903.toAudioString)

输出:2:11:43