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Swiftを使ったNSDateの比較

宿題の期限を確認する必要があるアプリに取り組んでいます。期限が来週以内かどうか、そしてそれが行動を起こすかどうかを知りたいのです。
私が見つけることができる文書の大部分はObjective-Cにあり、Swiftでそれを実行する方法を私は理解できません。助けてくれてありがとう！！

swiftnsdatexcode6
148
Henry oscannlain-miller

コードを読みやすくするために拡張機能を使うのが好きです。コードを整理して理解しやすくするための、NSDateの拡張機能をいくつか紹介します。これをsharedCode.Swiftファイルに入れます。

extension NSDate {

    func isGreaterThanDate(dateToCompare: NSDate) -> Bool {
        //Declare Variables
        var isGreater = false

        //Compare Values
        if self.compare(dateToCompare as Date) == ComparisonResult.orderedDescending {
            isGreater = true
        }

        //Return Result
        return isGreater
    }

    func isLessThanDate(dateToCompare: NSDate) -> Bool {
        //Declare Variables
        var isLess = false

        //Compare Values
        if self.compare(dateToCompare as Date) == ComparisonResult.orderedAscending {
            isLess = true
        }

        //Return Result
        return isLess
    }

    func equalToDate(dateToCompare: NSDate) -> Bool {
        //Declare Variables
        var isEqualTo = false

        //Compare Values
        if self.compare(dateToCompare as Date) == ComparisonResult.orderedSame {
            isEqualTo = true
        }

        //Return Result
        return isEqualTo
    }

    func addDays(daysToAdd: Int) -> NSDate {
        let secondsInDays: TimeInterval = Double(daysToAdd) * 60 * 60 * 24
        let dateWithDaysAdded: NSDate = self.addingTimeInterval(secondsInDays)

        //Return Result
        return dateWithDaysAdded
    }

    func addHours(hoursToAdd: Int) -> NSDate {
        let secondsInHours: TimeInterval = Double(hoursToAdd) * 60 * 60
        let dateWithHoursAdded: NSDate = self.addingTimeInterval(secondsInHours)

        //Return Result
        return dateWithHoursAdded
    }
}

今、あなたがこのようなことをすることができるならば：

//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...
}
185
user2266987

NSDatesに対して==、<、>、<=、または>=をサポートしたい場合は、これをどこかで宣言する必要があります。

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 { }
206
John Estropia

これがSwiftで2つのNSDateを比較する方法です。Xcodeのプレイグラウンドでテストしたところです。

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");
}

そのため、日付dueDateが今から1週間以内であるかどうかを確認します。

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)");
}
54
Undo

私はいつも一行でやった：

let greater = date1.timeIntervalSince1970 < date2.timeIntervalSince1970

ifブロック内でまだ読み取り可能

46
ReDetection

Swift3では、DateのFoundation構造体がComparableプロトコルを実装するようになりました。そのため、以前のSwift2のNSDateのアプローチは、Swift3のDateに置き換えられました。

/**
 `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 ...

Swift3では、Dateはstructであり、それはvalue typeであることを意味します。 NSDateはclass、それはreference typeです。

// 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`.
12
AechoLiu

Swift 3で日付を粒度（ちょうど同じ日や年など）と比較したい場合。

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
 }
}

他のカレンダー比較では、.dayをに変更します。

・年・月・日・時・分・秒

6
SashaZ
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
    }
}
6
Yura Voevodin

Swiftはすでにdate比較を実装しているだけで、date1> date2のようになります。

/// 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)
5
Trung Phan

swift 3では、日付は比較可能なので、次のように直接日付を比較できます。

let date1 = Date()
let date2 = Date()

let isGreater = date1 > date2
print(isGreater)

let isEqual = date1 == date2
print(isEqual)

または代わりに

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")
}

dateにextensionを作成するより良い方法

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
  }

}

使い方let isGreater = date1.isGreater(than: date2)

4
Suhit Patil

この関数は、1つの日付（startDate）が両方ともNSDate変数として定義されているendDateより後であるかどうかを比較するのに役立ちました。

if startDate.compare(endDate as Date) == ComparisonResult.orderedDescending
3
Diskprotek

Swiftでの実装

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
})
2
János
var dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
let dateData: String = dateFormatter.stringFromDate(date1)
let testDate: String = dateFormatter.stringFromDate(date2)
print(dateData == testDate)
2
Trevor Jordet

SashaZを拡張する

SwiftiOS 8以降単により大きなまたは小さな日付の比較以上のものが必要な場合。たとえば、同じ日や前日などです。

注：タイムゾーンを忘れないでください。カレンダーのタイムゾーンにはデフォルトがありますが、デフォルトが気に入らない場合は、タイムゾーンを自分で設定する必要があります。それが何日であることを知るために、あなたはあなたが尋ねているタイムゾーンを知る必要があります。

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)
        }
    }

このように使用してください。

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

もっと複雑な例です。 "findThisDay"と同じ日からの配列内のすべての日付を検索してフィルタ処理します。

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)) }
1
t1ser

Swift 3では、以下の関数を使って2つの日付を比較することができます。

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は、比較を適用したい制約に従って変更できます。

1
Himanshu

現在時刻を2回（2つの日付）でチェックするシナリオがあります。たとえば、診療所（病院）の開始時刻と終了時刻の間の現在の嘘をチェックしたいとします。

単純なコードを使用してください。

      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");
        }
1
Maninderjit Singh
someArray.sort({($0.dateAdded?.timeIntervalSinceReferenceDate)! < ($1.dateAdded?.timeIntervalSinceReferenceDate)!})

dateAddedは私のオブジェクトのNSDate変数です

class MyClass {
    let dateAdded: NSDate?
}
0
larod