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
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()
}
其他回答
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()
}
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: [])
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 ""
}
}
在Swift 2.2中
/// Returns the amount of years from another date
func years(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components([.Year], fromDate: fromdate, toDate: NSDate(), options: []).year ?? 0
}
/// Returns the amount of months from another date
func months(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components([.Month], fromDate: fromdate, toDate: NSDate(), options: []).month ?? 0
}
/// Returns the amount of weeks from another date
func weeks(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components([.WeekOfYear], fromDate: fromdate, toDate: NSDate(), options: []).weekOfYear ?? 0
}
/// Returns the amount of days from another date
func days(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components([.Day], fromDate: fromdate, toDate: NSDate(), options: []).day ?? 0
}
/// Returns the amount of hours from another date
func hours(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components([.Hour], fromDate: fromdate, toDate: NSDate(), options: []).hour ?? 0
}
/// Returns the amount of minutes from another date
func minutes(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components([.Minute], fromDate: fromdate, toDate: NSDate(), options: []).minute ?? 0
}
/// Returns the amount of seconds from another date
func seconds(fromdate: NSDate) -> Int {
return NSCalendar.currentCalendar().components(.Second, fromDate: fromdate, toDate: NSDate(), options: []).second ?? 0
}
我在Leo Dabus的asnwer中添加了一个“长”版本，以防你想要一个字符串，说“2周前”而不是“2w”……
extension Date {
func offsetLong(from date: Date) -> String {
if years(from: date) > 0 {
return years(from: date) > 1 ? "\(years(from: date)) years ago" : "\(years(from: date)) year ago"
}
if months(from: date) > 0 {
return months(from: date) > 1 ? "\(months(from: date)) months ago" : "\(months(from: date)) month ago"
}
if weeks(from: date) > 0 {
return weeks(from: date) > 1 ? "\(weeks(from: date)) weeks ago" : "\(weeks(from: date)) week ago"
}
if days(from: date) > 0 {
return days(from: date) > 1 ? "\(days(from: date)) days ago" : "\(days(from: date)) day ago"
}
if hours(from: date) > 0 {
return hours(from: date) > 1 ? "\(hours(from: date)) hours ago" : "\(hours(from: date)) hour ago"
}
if minutes(from: date) > 0 {
return minutes(from: date) > 1 ? "\(minutes(from: date)) minutes ago" : "\(minutes(from: date)) minute ago"
}
if seconds(from: date) > 0 {
return seconds(from: date) > 1 ? "\(seconds(from: date)) seconds ago" : "\(seconds(from: date)) second ago"
}
return ""
}
}
