NSDate比较使用Swift

我正在做一个应用程序，需要检查作业的到期date。 我想知道下个星期是否到期，如果是，那就执行一个动作。
我能find的大部分文档都在Objective-C中，我不知道如何在Swift中做到这一点。 谢谢您的帮助！！

Answer 1

我喜欢使用扩展来使代码更具可读性。 以下是一些NSDate扩展，可以帮助清理代码并使其易于理解。 我把它放在一个sharedCode.swift文件中：

 extension NSDate { func isGreaterThanDate(dateToCompare: NSDate) -> Bool { //Declare Variables var isGreater = false //Compare Values if self.compare(dateToCompare) == NSComparisonResult.OrderedDescending { isGreater = true } //Return Result return isGreater } func isLessThanDate(dateToCompare: NSDate) -> Bool { //Declare Variables var isLess = false //Compare Values if self.compare(dateToCompare) == NSComparisonResult.OrderedAscending { isLess = true } //Return Result return isLess } func equalToDate(dateToCompare: NSDate) -> Bool { //Declare Variables var isEqualTo = false //Compare Values if self.compare(dateToCompare) == NSComparisonResult.OrderedSame { isEqualTo = true } //Return Result return isEqualTo } func addDays(daysToAdd: Int) -> NSDate { let secondsInDays: NSTimeInterval = Double(daysToAdd) * 60 * 60 * 24 let dateWithDaysAdded: NSDate = self.dateByAddingTimeInterval(secondsInDays) //Return Result return dateWithDaysAdded } func addHours(hoursToAdd: Int) -> NSDate { let secondsInHours: NSTimeInterval = Double(hoursToAdd) * 60 * 60 let dateWithHoursAdded: NSDate = self.dateByAddingTimeInterval(secondsInHours) //Return Result return dateWithHoursAdded } } 

现在，如果你可以做这样的事情：

 //Get Current Date/Time var currentDateTime = NSDate() //Get Reminder Date (which is Due date minus 7 days lets say) var reminderDate = dueDate.addDays(-7) //Check if reminderDate is Greater than Right now if(reminderDate.isGreaterThanDate(currentDateTime)) { //Do Something... } 

Answer 2

如果你想为NSDate支持== ， < ， > ， <=或者>= ，你只需要在某处声明：

 public func ==(lhs: NSDate, rhs: NSDate) -> Bool { return lhs === rhs || lhs.compare(rhs) == .OrderedSame } public func <(lhs: NSDate, rhs: NSDate) -> Bool { return lhs.compare(rhs) == .OrderedAscending } extension NSDate: Comparable { } 

Answer 3

这是你如何比较Swift中的两个NSDate，我只是在Xcode的游乐场中testing它：

 if date1.compare(date2) == NSComparisonResult.OrderedDescending { NSLog("date1 after date2"); } else if date1.compare(date2) == NSComparisonResult.OrderedAscending { NSLog("date1 before date2"); } else { NSLog("dates are equal"); } 

所以要检查一个datedueDate是否在一个星期之内：

 let dueDate=... let calendar = NSCalendar.currentCalendar() let comps = NSDateComponents() comps.day = 7 let date2 = calendar.dateByAddingComponents(comps, toDate: NSDate(), options: NSCalendarOptions.allZeros) if dueDate.compare(date2!) == NSComparisonResult.OrderedDescending { NSLog("not due within a week"); } else if dueDate.compare(date2!) == NSComparisonResult.OrderedAscending { NSLog("due within a week"); } else { NSLog("due in exactly a week (to the second, this will rarely happen in practice)"); } 

Answer 4

我一直在做一行：

 let greater = date1.timeIntervalSince1970 < date2.timeIntervalSince1970 

仍然可以在if块中读取

Answer 5

在Swift3中， Foundation的Date结构现在实现了Comparable协议。 所以，之前的Swift2 NSDate方法被Swift3 Date取代。

 /** `Date` represents a single point in time. A `Date` is independent of a particular calendar or time zone. To represent a `Date` to a user, you must interpret it in the context of a `Calendar`. */ public struct Date : ReferenceConvertible, Comparable, Equatable { // .... more /** Returns the interval between the receiver and another given date. - Parameter another: The date with which to compare the receiver. - Returns: The interval between the receiver and the `another` parameter. If the receiver is earlier than `anotherDate`, the return value is negative. If `anotherDate` is `nil`, the results are undefined. - SeeAlso: `timeIntervalSince1970` - SeeAlso: `timeIntervalSinceNow` - SeeAlso: `timeIntervalSinceReferenceDate` */ public func timeIntervalSince(_ date: Date) -> TimeInterval // .... more /// Returns true if the two `Date` values represent the same point in time. public static func ==(lhs: Date, rhs: Date) -> Bool /// Returns true if the left hand `Date` is earlier in time than the right hand `Date`. public static func <(lhs: Date, rhs: Date) -> Bool /// Returns true if the left hand `Date` is later in time than the right hand `Date`. public static func >(lhs: Date, rhs: Date) -> Bool /// Returns a `Date` with a specified amount of time added to it. public static func +(lhs: Date, rhs: TimeInterval) -> Date /// Returns a `Date` with a specified amount of time subtracted from it. public static func -(lhs: Date, rhs: TimeInterval) -> Date // .... more } 

注意 …

在Swift3中， Date是struct ，这意味着它是value type 。 NSDate是class ，它是reference type 。

 // Swift3 let a = Date() let b = a //< `b` will copy `a`. // So, the addresses between `a` and `b` are different. // `Date` is some kind different with `NSDate`. 

Answer 6

 extension NSDate { // MARK: - Dates comparison func isGreaterThanDate(dateToCompare: NSDate) -> Bool { return self.compare(dateToCompare) == NSComparisonResult.OrderedDescending } func isLessThanDate(dateToCompare: NSDate) -> Bool { return self.compare(dateToCompare) == NSComparisonResult.OrderedAscending } func equalToDate(dateToCompare: NSDate) -> Bool { return self.compare(dateToCompare) == NSComparisonResult.OrderedSame } } 

Answer 7

如果你想比较date与粒度（只是同一天或年份等）在SWIFT 3。

 func compareDate(date1:NSDate, date2:NSDate, toUnitGranularity: NSCalendar.Unit) -> Bool { let order = NSCalendar.current.compare(date1 as Date, to: date2 as Date, toGranularity: .day) switch order { case .orderedSame: return true default: return false } } 

对于其他日历比较更改。天到;

。年。月。日。小时。分。秒

Answer 8

Swift已经实现了Date比较只是使用date1> date2等等。

 /// Returns true if the two `Date` values represent the same point in time. public static func ==(lhs: Date, rhs: Date) -> Bool /// Returns true if the left hand `Date` is earlier in time than the right hand `Date`. public static func <(lhs: Date, rhs: Date) -> Bool /// Returns true if the left hand `Date` is later in time than the right hand `Date`. public static func >(lhs: Date, rhs: Date) -> Bool /// Returns a `Date` with a specified amount of time added to it. public static func +(lhs: Date, rhs: TimeInterval) -> Date /// Returns a `Date` with a specified amount of time subtracted from it. public static func -(lhs: Date, rhs: TimeInterval) -> Date /// Add a `TimeInterval` to a `Date`. /// /// - warning: This only adjusts an absolute value. If you wish to add calendrical concepts like hours, days, months then you must use a `Calendar`. That will take into account complexities like daylight saving time, months with different numbers of days, and more. public static func +=(lhs: inout Date, rhs: TimeInterval) /// Subtract a `TimeInterval` from a `Date`. /// /// - warning: This only adjusts an absolute value. If you wish to add calendrical concepts like hours, days, months then you must use a `Calendar`. That will take into account complexities like daylight saving time, months with different numbers of days, and more. public static func -=(lhs: inout Date, rhs: TimeInterval) 

Answer 9

在Swift 3中，Date是Comparable，所以我们可以直接比较date

 let date1 = Date() let date2 = Date() let isGreater = date1 > date2 print(isGreater) let isEqual = date1 == date2 print(isEqual) 

或者可选地

 let result = date1.compare(date2) switch result { case .OrderedAscending : print("date 1 is earlier than date 2") case .OrderedDescending : print("date 1 is later than date 2") case .OrderedSame : print("two dates are the same") } 

更好的方式创builddate的extension

 extension Date { fun isGreater(than date: Date) -> Bool { return self > date } func isSmaller(than date: Date) -> Bool { return self < date } func isEqual(to date: Date) -> Bool { return self == date } } 

用法let isGreater = date1.isGreater(than: date2)

Answer 10

这个函数为我比较是否一个date（startDate）是在endDate之后，其中两个被定义为NSDatevariables：

 if startDate.compare(endDate as Date) == ComparisonResult.orderedDescending 

Answer 11

在Swift实现

 let documentsPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as NSString let files = NSFileManager.defaultManager().contentsOfDirectoryAtPath(documentsPath, error: nil) let filesAndProperties = NSMutableArray() for file in files! { let filePath = documentsPath.stringByAppendingString(file as NSString) let properties = NSFileManager.defaultManager().attributesOfItemAtPath(filePath, error: nil) let modDate = properties![NSFileModificationDate] as NSDate filesAndProperties.addObject(NSDictionary(objectsAndKeys: file, "path", modDate, "lastModDate")) } let sortedFiles = filesAndProperties.sortedArrayUsingComparator({ (path1, path2) -> NSComparisonResult in var comp = (path1.objectForKey("lastModDate") as NSDate).compare(path2.objectForKey("lastModDate") as NSDate) if comp == .OrderedDescending { comp = .OrderedAscending } else if comp == .OrderedAscending { comp = .OrderedDescending } return comp }) 

Answer 12

 var dateFormatter = NSDateFormatter() dateFormatter.dateFormat = "yyyy-MM-dd" let dateData: String = dateFormatter.stringFromDate(date1) let testDate: String = dateFormatter.stringFromDate(date2) print(dateData == testDate) 

Answer 13

我们有检查当前时间的情况，谎言是两次（两个date）。例如，我想检查当前在诊所（医院）开放时间和closures时间之间的谎言。

使用简单的代码。

  NSDate * now = [NSDate date]; NSDateFormatter *outputFormatter = [[NSDateFormatter alloc] init]; [outputFormatter setDateFormat:@"HH:mm:ss"]; //current time NSString *currentTimeString = [outputFormatter stringFromDate:now]; NSDate *dateCurrent = [outputFormatter dateFromString:currentTimeString]; NSString *timeStart = @"09:00:00"; NSString *timeEnd = @"22:00:00"; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setDateFormat:@"HH:mm:ss"]; NSDate *dateStart= [formatter timeStart]; NSDate *dateEnd = [formatter timeEnd]; NSComparisonResult result = [dateCurrent compare:dateStart]; NSComparisonResult resultSecond = [date2 compare:dateEnd]; if(result == NSOrderedDescending && resultSecond == NSOrderedDescending) { NSLog(@"current time lies in starting and end time"); }else { NSLog(@"current time doesn't lie in starting and end time"); } 

Answer 14

对于swift 3，你可以使用下面的函数来比较两个date。

 func compareDate(dateInitial:Date, dateFinal:Date) -> Bool { let order = Calendar.current.compare(dateInitial, to: dateFinal, toGranularity: .day) switch order { case .orderedSame: return true default: return false } } 

toGranularity可以根据你想要应用你的比较的约束来改变。

Answer 15

延长SashaZ

Swift iOS 8及更高版本当您不仅仅需要更大或更小的date比较时。 例如，是同一天还是前一天，…

注意：永远不要忘记时区。 日历时区有一个默认的，但如果你不喜欢默认，你必须自己设置时区。 要知道哪一天，你需要知道你在问什么时区。

 extension Date { func compareTo(date: Date, toGranularity: Calendar.Component ) -> ComparisonResult { var cal = Calendar.current cal.timeZone = TimeZone(identifier: "Europe/Paris")! return cal.compare(self, to: date, toGranularity: toGranularity) } } 

像这样使用它：

 if thisDate.compareTo(date: Date(), toGranularity: .day) == .orderedDescending { // thisDate is a previous day } 

一个更复杂的例子。 查找并过滤与“findThisDay”同一天的数组中的所有date：

 let formatter = DateFormatter() formatter.timeZone = TimeZone(identifier: "Europe/Paris") formatter.dateFormat = "yyyy/MM/dd HH:mm:ss" let findThisDay = formatter.date(from: "2018/11/05 08:11:08")! _ = [ formatter.date(from: "2018/12/05 08:08:08")!, formatter.date(from: "2018/11/05 08:11:08")!, formatter.date(from: "2018/11/05 11:08:22")!, formatter.date(from: "2018/11/05 22:08:22")!, formatter.date(from: "2018/11/05 08:08:22")!, formatter.date(from: "2018/11/07 08:08:22")!, ] .filter{ findThisDay.compareTo(date: $0 , toGranularity: .day) == .orderedSame } .map { print(formatter.string(from: $0)) } 

Answer 16

 someArray.sort({($0.dateAdded?.timeIntervalSinceReferenceDate)! < ($1.dateAdded?.timeIntervalSinceReferenceDate)!}) 

dateAdded是我的对象中的一个NSDatevariables

 class MyClass { let dateAdded: NSDate? }