Swift 在 Unix 时间戳上使用 DateFormatter

我 run 时撞车，它指向dateFormmater.timezone.

无法强制转换类型为"Swift"的值.可选"(0x1192bf4a8)至"NSTimeZone"(0x1192c0270).

rowEvents.date的值是"1480134638.0"

我正试图从Firebase中取出一个保存为字符串的Unix时间戳.将其转换为日期，然后再次将其保存为字符串，以便我可以将其发布到单元格标签上.

我从StackOverflow那里得到了这个密码.我插入了我的数据，一切都很好，直到我运行它.我想不是所有的事情都好...

if let lastUpdated : String = rowEvents.date {

    let epocTime = TimeInterval(lastUpdated)! / 1000 // convert it from milliseconds dividing it by 1000

    let unixTimestamp = NSDate(timeIntervalSince1970: epocTime) //convert unix timestamp to Date

    let dateFormatter = DateFormatter()
    dateFormatter.timeZone = NSTimeZone() as TimeZone!
    dateFormatter.locale = NSLocale.current // NSLocale(localeIdentifier: "en_US_POSIX")
    dateFormatter.dateFormat =  "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
    dateFormatter.date(from: String(describing: unixTimestamp))

    let updatedTimeStamp = unixTimestamp
    let cellDate = DateFormatter.localizedString(from: updatedTimeStamp as Date, dateStyle: DateFormatter.Style.full, timeStyle: DateFormatter.Style.medium)

    cell.subtitleLabel.text = cellDate              
}

结果来自以下代码:

let myTimeStamp = self.datePicker?.date.timeIntervalSince1970

let calendarDate = String(describing: myTimeStamp! /** 1000*/)