swift - 如何检查是否已经过了 3 天

Question

如何检查每 3 天下载一些数据？我需要做的就是检查用户打开应用程序时是否已经过了 3 天或更长时间，如果是，应用程序是否可以下载一些东西？到目前为止，这是我比较日期的内容:

var shouldDownload: Bool = false

extension NSDate: Equatable {}
extension NSDate: Comparable {}

public func ==(lhs: NSDate, rhs: NSDate) -> Bool {
    return lhs.timeIntervalSince1970 == rhs.timeIntervalSince1970
}    

public func <(lhs: NSDate, rhs: NSDate) -> Bool {
    return lhs.timeIntervalSince1970 < rhs.timeIntervalSince1970
}

extension Int {
    var days: NSTimeInterval {
        let DAY_IN_SECONDS = 60 * 60 * 24
        var days:Double = Double(DAY_IN_SECONDS) * Double(self)
        return days
}
let lastChecked = NSDate()

let interval = NSDate(timeInterval: 3.days, sinceDate: lastChecked)
let today = NSDate()

if interval > today {
    shouldDownload = true
}

Answer 1

您可以使用这个简单的函数:

func isPassedMoreThan(days: Int, fromDate date : Date, toDate date2 : Date) -> Bool {
    let unitFlags: Set<Calendar.Component> = [.day]
    let deltaD = Calendar.current.dateComponents( unitFlags, from: date, to: date2).day
    return (deltaD ?? 0 > days)
}