iOS swift 。自日期以来的时间

Question

我想要自给定日期以来的月数和天数，由字符串给出。

d是一个日期字符串

    let dateFormatter = NSDateFormatter()
    dateFormatter.dateFormat = "MM-dd-yy"
    let date = dateFormatter.dateFromString(d)
    startTime = date?.timeIntervalSinceReferenceDate

理想情况下，我希望自日期以来的月、日、分钟，但一旦我通过此错误，我将处理该部分。编译器提示最后一行。

谢谢

Answer 1

您需要使用 NSCalendar 来计算月份和日期的差异。示例:

let calendar = NSCalendar.autoupdatingCurrentCalendar()
calendar.timeZone = NSTimeZone.systemTimeZone()
let dateFormatter = NSDateFormatter()
dateFormatter.timeZone = calendar.timeZone
dateFormatter.dateFormat = "yyyy-MM-dd"
if let startDate = dateFormatter.dateFromString("2014-9-15") {
    let components = calendar.components([ .Month, .Day ],
        fromDate: startDate, toDate: NSDate(), options: [])
    let months = components.month
    let days = components.day
    print("It's been \(months) months and \(days) days.")
}

输出(2014-01-05):

It's been 3 months and 21 days.