时间转化
let timeTextIndex = model.expireDatetime?.endIndex.advancedBy(-cutTimeIndex)
let timeString = model.expireDatetime?.substringToIndex(timeTextIndex!)
let dateFormat = NSDateFormatter()
//2016-08-05 00:58:35.0
dateFormat.dateFormat = "yyyy-MM-dd HH:mm:ss"
let expireTime = dateFormat.dateFromString(timeString!)//很明显的 正则表达式)
let carlendar = NSCalendar.currentCalendar()
let unitFlags = NSCalendarUnit(rawValue: NSCalendarUnit.Hour.rawValue | NSCalendarUnit.Minute.rawValue | NSCalendarUnit.Second.rawValue )
let dateTimeNeeds = carlendar.components(unitFlags, fromDate: NSDate(), toDate: expireTime!, options: NSCalendarOptions(rawValue: 0) )
/*
第一个参数:需要计算年月日时分秒里面的哪一项
第二个参数:开始时间
第三个参数:结束时间
第四个参数:选项
*/
self.timeLabel?.text = String(format: "剩余 %2d: %02d: %02d .", dateTimeNeeds.hour, dateTimeNeeds.minute, dateTimeNeeds.second)
