Swift - 用秒数-转换-天时分秒

 //MARK: -时间戳转时间函数
    func timeStampToString(timeStamp: Int)->String {
        ///天
        let days = Int(timeStamp/(3600*24)) 
        ///时
        let hours = Int((timeStamp - days*24*3600)/3600)
        ///分
        let minute = Int((timeStamp - days*24*3600-hours*3600)/60)
        ///秒
        let second = Int((timeStamp - days*24*3600-hours*3600) - 60*minute)
        let timeString = String.init(format: "%d:%d",hours,minute)
        return timeString
    }