我试图得到当前日期之间的差异作为NSDate()和日期从一个PHP时间();调用例如:NSDate(timeintervalsincerely eferencedate: 1417147270)。我怎样才能得到这两个日期之间的时间差呢?我想有一个函数，比较两个日期，如果(秒> 60)，那么它返回分钟，如果(分钟> 60)返回小时，如果(小时> 24)返回天，等等。
我该怎么做呢?
编辑:目前接受的答案完全符合我的想法。为了便于使用，我推荐使用它，以便以PHP time()函数使用的形式获取两个日期之间的时间。如果你不是特别熟悉PHP，这是1970年1月1日的时间，单位是秒。这对于PHP的后端是有益的。如果你正在使用像NodeJS这样的后端，你可能会考虑下面的其他选项。
当前回答
如果有人需要显示所有的时间单位，如“小时分秒”，而不仅仅是“小时”。假设两个日期的时差是1小时59分20秒。该功能将显示“1h 59m 20s”。
下面是我的Objective-C代码:
extension NSDate {
func offsetFrom(date: NSDate) -> String {
let dayHourMinuteSecond: NSCalendarUnit = [.Day, .Hour, .Minute, .Second]
let difference = NSCalendar.currentCalendar().components(dayHourMinuteSecond, fromDate: date, toDate: self, options: [])
let seconds = "\(difference.second)s"
let minutes = "\(difference.minute)m" + " " + seconds
let hours = "\(difference.hour)h" + " " + minutes
let days = "\(difference.day)d" + " " + hours
if difference.day > 0 { return days }
if difference.hour > 0 { return hours }
if difference.minute > 0 { return minutes }
if difference.second > 0 { return seconds }
return ""
}
}
在Swift 3+中:
extension Date {
func offsetFrom(date: Date) -> String {
let dayHourMinuteSecond: Set<Calendar.Component> = [.day, .hour, .minute, .second]
let difference = NSCalendar.current.dateComponents(dayHourMinuteSecond, from: date, to: self)
let seconds = "\(difference.second ?? 0)s"
let minutes = "\(difference.minute ?? 0)m" + " " + seconds
let hours = "\(difference.hour ?? 0)h" + " " + minutes
let days = "\(difference.day ?? 0)d" + " " + hours
if let day = difference.day, day > 0 { return days }
if let hour = difference.hour, hour > 0 { return hours }
if let minute = difference.minute, minute > 0 { return minutes }
if let second = difference.second, second > 0 { return seconds }
return ""
}
}
其他回答
如果有人需要显示所有的时间单位，如“小时分秒”，而不仅仅是“小时”。假设两个日期的时差是1小时59分20秒。该功能将显示“1h 59m 20s”。
下面是我的Objective-C代码:
extension NSDate {
func offsetFrom(date: NSDate) -> String {
let dayHourMinuteSecond: NSCalendarUnit = [.Day, .Hour, .Minute, .Second]
let difference = NSCalendar.currentCalendar().components(dayHourMinuteSecond, fromDate: date, toDate: self, options: [])
let seconds = "\(difference.second)s"
let minutes = "\(difference.minute)m" + " " + seconds
let hours = "\(difference.hour)h" + " " + minutes
let days = "\(difference.day)d" + " " + hours
if difference.day > 0 { return days }
if difference.hour > 0 { return hours }
if difference.minute > 0 { return minutes }
if difference.second > 0 { return seconds }
return ""
}
}
在Swift 3+中:
extension Date {
func offsetFrom(date: Date) -> String {
let dayHourMinuteSecond: Set<Calendar.Component> = [.day, .hour, .minute, .second]
let difference = NSCalendar.current.dateComponents(dayHourMinuteSecond, from: date, to: self)
let seconds = "\(difference.second ?? 0)s"
let minutes = "\(difference.minute ?? 0)m" + " " + seconds
let hours = "\(difference.hour ?? 0)h" + " " + minutes
let days = "\(difference.day ?? 0)d" + " " + hours
if let day = difference.day, day > 0 { return days }
if let hour = difference.hour, hour > 0 { return hours }
if let minute = difference.minute, minute > 0 { return minutes }
if let second = difference.second, second > 0 { return seconds }
return ""
}
}
对于XCode版本8.3.3和Swift 3.0:
let dateFormatter = DateFormatter()
dateFormatter.dateStyle = .medium
dateFormatter.timeStyle = .short
var beginDate = "2017-08-24 12:00:00"
var endDate = "2017-09-07 12:00:00"
let startDateTime = dateFormatter.date(from: beginDate) //according to date format your date string
print(startDateTime ?? "") //Convert String to Date
let endDateTime = dateFormatter.date(from: endDate) //according to date format your date string
print(endDateTime ?? "") //Convert String to Date
let dateComponentsFormatter = DateComponentsFormatter()
dateComponentsFormatter.allowedUnits = [NSCalendar.Unit.minute,NSCalendar.Unit.hour,NSCalendar.Unit.day]
let interval = endDateTime!.timeIntervalSince(startDateTime!)
var diff = dateComponentsFormatter.string(from: interval)!
print(diff)
var day_i = 0
var hour_i = 0
var min_i = 0
if (diff.contains("d"))
{
let day = diff.substring(to: (diff.range(of: "d")?.lowerBound)!)
day_i = Int(day)!
print ("day --> \(day_i)")
diff = diff.substring(from:(diff.range(of : " ")?.upperBound )!)
print(diff)
}
let hour = diff.substring(to: (diff.range(of : ":")?.lowerBound )!)
hour_i = Int(hour)!
print ("hour --> \(hour_i)")
let min = diff.substring(from: (diff.range(of : ":")?.upperBound )!)
min_i = Int(min)!
print ("min --> \(min_i)")
你问:
我想有一个函数，比较两个日期，如果(秒> 60)，那么它返回分钟，如果(分钟> 60)返回小时，如果(小时> 24)返回天，等等。
我假设您正在尝试构建两个日期之间经过时间的字符串表示。而不是自己写代码来做这件事，苹果已经有了一个专门设计来做这件事的类。也就是说，使用DateComponentsFormatter，将allowedUnits设置为对你的应用有意义的任何值，将unitsStyle设置为你想要的任何值(例如.full)，然后调用string(from:to:)。
例如，在Swift 3中:
let previousDate = ...
let now = Date()
let formatter = DateComponentsFormatter()
formatter.unitsStyle = .full
formatter.allowedUnits = [.month, .day, .hour, .minute, .second]
formatter.maximumUnitCount = 2 // often, you don't care about seconds if the elapsed time is in months, so you'll set max unit to whatever is appropriate in your case
let string = formatter.string(from: previousDate, to: now)
这也将本地化对应于相关设备的字符串。
或者，在Swift 2.3中:
let previousDate = ...
let now = NSDate()
let formatter = NSDateComponentsFormatter()
formatter.unitsStyle = .Full
formatter.allowedUnits = [.Month, .Day, .Hour, .Minute, .Second]
formatter.maximumUnitCount = 2
let string = formatter.stringFromDate(previousDate, toDate: now)
如果您正在寻找实际的数值，只需使用dateComponents。例如，在Swift 3中:
let components = Calendar.current.dateComponents([.month, .day, .hour, .minute, .second], from: previousDate, to: now)
或者，在Swift 2.3中:
let components = NSCalendar.currentCalendar().components([.Month, .Day, .Hour, .Minute, .Second], fromDate: previousDate, toDate: now, options: [])
import Foundation
extension DateComponents {
func dateComponentsToTimeString() -> String {
var hour = "\(self.hour!)"
var minute = "\(self.minute!)"
var second = "\(self.second!)"
if self.hour! < 10 { hour = "0" + hour }
if self.minute! < 10 { minute = "0" + minute }
if self.second! < 10 { second = "0" + second }
let str = "\(hour):\(minute):\(second)"
return str
}
}
extension Date {
func offset(from date: Date)-> DateComponents {
let components = Set<Calendar.Component>([.second, .minute, .hour, .day, .month, .year])
let differenceOfDate = Calendar.current.dateComponents(components, from: date, to: self)
return differenceOfDate
}
}
Use:
var durationString: String {
return self.endTime.offset(from: self.startTime).dateComponentsToTimeString()
}
如果你的目的是获得两个日期之间的确切天数，你可以这样解决这个问题:
// Assuming that firstDate and secondDate are defined
// ...
var calendar: NSCalendar = NSCalendar.currentCalendar()
// Replace the hour (time) of both dates with 00:00
let date1 = calendar.startOfDayForDate(firstDate)
let date2 = calendar.startOfDayForDate(secondDate)
let flags = NSCalendarUnit.DayCalendarUnit
let components = calendar.components(flags, fromDate: date1, toDate: date2, options: nil)
components.day // This will return the number of day(s) between dates
