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swiftで現在の週の月曜日の日付を取得する方法

私は今週の月曜日の日付を取得しようとしています。これは、テーブルビューで週の最初の日として扱われます。また、今週の日曜日を取得する必要があります。これは、テーブルビューでは週の最後の日として扱われます。

現在の試み：

let date = NSDate()
let calendar = NSCalendar.currentCalendar()
calendar.firstWeekday = 1
//attempt to changefirstday

let dateFormatter = NSDateFormatter()
let theDateFormat = NSDateFormatterStyle.ShortStyle
let theTimeFormat = NSDateFormatterStyle.ShortStyle
dateFormatter.dateStyle = theDateFormat
dateFormatter.timeStyle = theTimeFormat

let currentDateComponents = calendar.components([.YearForWeekOfYear, .WeekOfYear ], fromDate: date)
let startOfWeek = calendar.dateFromComponents(currentDateComponents)
print("startOfWeek is \(startOfWeek)")
let stringDate = dateFormatter.stringFromDate(startOfWeek!)
print("string date is \(stringDate)") //This is returning Sunday's date
swiftdatenscalendar
16
user2363025

特定の曜日の日付を取得するために日付拡張機能を作成しました。Swift 4、

Date.today().next(.monday)                    // Feb 12, 2018 at 12:00 AM
Date.today().next(.sunday)                    //  Feb 11, 2018 at 12:00 AM


Date.today().previous(.sunday)                // Feb 4, 2018 at 12:00 AM
Date.today().previous(.monday)                // Feb 5, 2018 at 12:00 AM

Date.today().previous(.thursday)              // Feb 1, 2018 at 12:00 AM
Date.today().next(.thursday)                  // Feb 15, 2018 at 12:00 AM
Date.today().previous(.thursday,
                      considerToday: true)    // Feb 8, 2018 at 11:04 PM


Date.today().next(.monday)
            .next(.sunday)
            .next(.thursday)                  // Feb 22, 2018 at 12:00 AM

そして、これはそのための日付拡張です、

extension Date {

  static func today() -> Date {
      return Date()
  }

  func next(_ weekday: Weekday, considerToday: Bool = false) -> Date {
    return get(.Next,
               weekday,
               considerToday: considerToday)
  }

  func previous(_ weekday: Weekday, considerToday: Bool = false) -> Date {
    return get(.Previous,
               weekday,
               considerToday: considerToday)
  }

  func get(_ direction: SearchDirection,
           _ weekDay: Weekday,
           considerToday consider: Bool = false) -> Date {

    let dayName = weekDay.rawValue

    let weekdaysName = getWeekDaysInEnglish().map { $0.lowercased() }

    assert(weekdaysName.contains(dayName), "weekday symbol should be in form \(weekdaysName)")

    let searchWeekdayIndex = weekdaysName.index(of: dayName)! + 1

    let calendar = Calendar(identifier: .gregorian)

    if consider && calendar.component(.weekday, from: self) == searchWeekdayIndex {
      return self
    }

    var nextDateComponent = DateComponents()
    nextDateComponent.weekday = searchWeekdayIndex


    let date = calendar.nextDate(after: self,
                                 matching: nextDateComponent,
                                 matchingPolicy: .nextTime,
                                 direction: direction.calendarSearchDirection)

    return date!
  }

}

// MARK: Helper methods
extension Date {
  func getWeekDaysInEnglish() -> [String] {
    var calendar = Calendar(identifier: .gregorian)
    calendar.locale = Locale(identifier: "en_US_POSIX")
    return calendar.weekdaySymbols
  }

  enum Weekday: String {
    case monday, tuesday, wednesday, thursday, friday, saturday, sunday
  }

  enum SearchDirection {
    case Next
    case Previous

    var calendarSearchDirection: Calendar.SearchDirection {
      switch self {
      case .Next:
        return .forward
      case .Previous:
        return .backward
      }
    }
  }
}
54
Sandeep

最初の平日が月曜日であるカレンダーISO8601を使用できます。

Swift 3以降

var mondaysDate: Date {
    return Calendar(identifier: .iso8601).date(from: Calendar(identifier: .iso8601).dateComponents([.yearForWeekOfYear, .weekOfYear], from: Date()))!
}

print(mondaysDate.description(with: .current))   // Monday, July 16, 2018 at 12:00:00 AM Brasilia Standard Time"

拡張として：

extension Calendar {
    static let iso8601 = Calendar(identifier: .iso8601)
}

extension Date {
    var currentWeekMonday: Date {
        return Calendar.iso8601.date(from: Calendar.iso8601.dateComponents([.yearForWeekOfYear, .weekOfYear], from: self))!
    }
}

let currentWeekMonday = Date().currentWeekMonday
print(currentWeekMonday.description(with: .current)) // Monday, July 16, 2018 at 12:00:00 AM Brasilia Standard Time
27
Leo Dabus

私が作成した拡張機能は次のとおりです。最初に日曜日を検出し、次に1日追加します

extension Date {  
    var startOfWeek: Date? {
        let gregorian = Calendar(identifier: .gregorian)
        guard let sunday = gregorian.date(from: gregorian.dateComponents([.yearForWeekOfYear, .weekOfYear], from: self)) else { return nil }
        return gregorian.date(byAdding: .day, value: 1, to: sunday)
    }
}
8
Andy Norcisa

Sandeepの答え の簡易版を次に示します。

使用法：

Date().next(.monday)
Date().next(.monday, considerToday: true)
Date().next(.monday, direction: .backward)

拡張：

public func next(_ weekday: Weekday,
                 direction: Calendar.SearchDirection = .forward,
                 considerToday: Bool = false) -> Date
{
    let calendar = Calendar(identifier: .gregorian)
    let components = DateComponents(weekday: weekday.rawValue)

    if considerToday &&
        calendar.component(.weekday, from: self) == weekday.rawValue
    {
        return self
    }

    return calendar.nextDate(after: self,
                             matching: components,
                             matchingPolicy: .nextTime,
                             direction: direction)!
}

public enum Weekday: Int {
    case sunday = 1, monday, tuesday, wednesday, thursday, friday, saturday
}
8
John

使用してみてください：

_calendar.firstWeekday = 2
_

編集

具体的には：NSCalendar.currentCalendar()はユーザーカレンダーを返します。ドキュメントによると：

返されるカレンダーは、現在のユーザーが選択したシステムロケールの設定に、ユーザーがシステム環境設定で指定したカスタム設定を重ねて作成されます。

常に月曜日を初日にしたい場合は、次を使用する必要があると思います。

_let calendar = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)!
calendar!.firstWeekday = 2
_
3
zuziaka

@ Saneep回答への追加

指定された/現在の日付ごとに正確なdateTimeを取得する場合（月曜日のdateTimeを変換したい場合-> 23-05-2016 12:00:00から23-05-2016 05:35:17）次にこれを試してください：

func convertDate(date: NSDate, toGivendate: NSDate) -> NSDate {
    let calendar = NSCalendar.currentCalendar()
    let comp = calendar.components([.Year, .Month, .Day, .Hour, .Minute, .Second], fromDate: toGivendate)
    let hour = comp.hour
    let minute = comp.minute
    let second = comp.second

    let dateComp = calendar.components([.Year, .Month, .Day], fromDate: date)
    let year = dateComp.year
    let month = dateComp.month
    let day = dateComp.day

    let components = NSDateComponents()
    components.year = year
    components.month = month
    components.day = day
    components.hour = hour
    components.minute = minute
    components.second = second

    let newConvertedDate = calendar.dateFromComponents(components)

    return newConvertedDate!
}
1
Muhammad Umair

Swift 4ソリューション

私は自分の要件に従って、フォローする日付を見つけました。

1. Today

2. Tomorrow 

3. This Week 

4. This Weekend 

5. Next Week 

6. Next Weekend

だから、Date Extensionは、今週と来週の日付を取得します。

[〜＃〜] code [〜＃〜]

extension Date {

    func getWeekDates() -> (thisWeek:[Date],nextWeek:[Date]) {
        var Tuple: (thisWeek:[Date],nextWeek:[Date])
        var arrThisWeek: [Date] = []
        for i in 0..<7 {
            arrThisWeek.append(Calendar.current.date(byAdding: .day, value: i, to: startOfWeek)!)
        }
        var arrNextWeek: [Date] = []
        for i in 1...7 {
            arrNextWeek.append(Calendar.current.date(byAdding: .day, value: i, to: arrThisWeek.last!)!)
        }
        Tuple = (thisWeek: arrThisWeek,nextWeek: arrNextWeek)
        return Tuple
    }

    var tomorrow: Date {
        return Calendar.current.date(byAdding: .day, value: 1, to: noon)!
    }
    var noon: Date {
        return Calendar.current.date(bySettingHour: 12, minute: 0, second: 0, of: self)!
    }

    var startOfWeek: Date {
        let gregorian = Calendar(identifier: .gregorian)
        let sunday = gregorian.date(from: gregorian.dateComponents([.yearForWeekOfYear, .weekOfYear], from: self))
        return gregorian.date(byAdding: .day, value: 1, to: sunday!)!
    }

    func toDate(format: String) -> String {
        let formatter = DateFormatter()
        formatter.dateFormat = format
        return formatter.string(from: self)
    }
}

使用法：

let arrWeekDates = Date().getWeekDates() // Get dates of Current and Next week.
let dateFormat = "MMM dd" // Date format
let thisMon = arrWeekDates.thisWeek.first!.toDate(format: dateFormat)
let thisSat = arrWeekDates.thisWeek[arrWeekDates.thisWeek.count - 2].toDate(format: dateFormat)
let thisSun = arrWeekDates.thisWeek[arrWeekDates.thisWeek.count - 1].toDate(format: dateFormat)

let nextMon = arrWeekDates.nextWeek.first!.toDate(format: dateFormat)
let nextSat = arrWeekDates.nextWeek[arrWeekDates.nextWeek.count - 2].toDate(format: dateFormat)
let nextSun = arrWeekDates.nextWeek[arrWeekDates.nextWeek.count - 1].toDate(format: dateFormat)

print("Today: \(Date().toDate(format: dateFormat))") // Sep 26
print("Tomorrow: \(Date().tomorrow.toDate(format: dateFormat))") // Sep 27
print("This Week: \(thisMon) - \(thisSun)") // Sep 24 - Sep 30
print("This Weekend: \(thisSat) - \(thisSun)") // Sep 29 - Sep 30
print("Next Week: \(nextMon) - \(nextSun)") // Oct 01 - Oct 07
print("Next Weekend: \(nextSat) - \(nextSun)") // Oct 06 - Oct 07

必要に応じてExtensionを変更できます。

ありがとう！

0
Rashesh Bosamiya