swift-根据时间获得时间戳 13位

    /**
    根据时间获得时间戳 13位
   
    :param: dateStr 要转换的时间
   
    :returns: 时间戳
    */
   @objc class func getTimestampWithTime(_ dateStr: NSString) -> NSString
    {
        var strTime: NSString?
        if dateStr.length > 19
        {
            strTime = dateStr.substring(to: 19) as NSString?
        }
        else
        {
            strTime = dateStr
        }
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
        let date: Date = formatter.date(from: strTime! as String)!
//        println(date)
        let t = date.timeIntervalSince1970 * 1000
//        println(t)
        var timestamp: NSString = "\(t)" as NSString
        timestamp = timestamp.substring(to: timestamp.length - 2) as NSString
//        println(timestamp)
        return timestamp
    }