如何获得当月的开始日期和结束日期(Swift 3)

I'm trying to get the start and end dates of the current month in dd/MM/yyyy format. I tried using extension as answered in this SO Question.But it seems like it's not what I want(the format is different and also it's giving me last month's last date and current month last but one date ). Can some one help me.

我正在尝试以dd/MM/yyyy格式开始和结束当前月份的日期。我试着用扩展来回答这个问题。但它似乎不是我想要的(格式不同，而且它给了我上个月的最后一个日期和上一个月的最后一个日期)。有人能帮我吗?

Extension Class:

扩展类:

extension Date {
    func startOfMonth() -> Date? {
        let comp: DateComponents = Calendar.current.dateComponents([.year, .month, .hour], from: Calendar.current.startOfDay(for: self))
        return Calendar.current.date(from: comp)!
    }

    func endOfMonth() -> Date? {
        var comp: DateComponents = Calendar.current.dateComponents([.month, .day, .hour], from: Calendar.current.startOfDay(for: self))
        comp.month = 1
        comp.day = -1
        return Calendar.current.date(byAdding: comp, to: self.startOfMonth()!)
    }
}

My Struct:

我的结构:

struct Constants{

    // keys required for making a Login call (POST Method)
    struct LoginKeys {
       .....
    }

    struct RankingKeys {

        static let DateFrom = String(describing: Date().startOfMonth()) //giving me 2016-11-30 16:00:00 +0000 
        static let DateTo  = String(describing: Date().endOfMonth())
//2016-12-30 16:00:00 +0000
    }
}

Expected Result:

预期结果:

DateFrom  = "01/12/2016"
DateTo = "31/12/2016"

4 个解决方案

#1

You should write this simple code:

您应该编写以下简单的代码:

let dateFormatter = DateFormatter()
let date = Date()
dateFormatter.dateFormat = "dd-MM-yyyy"

For start Date:

开始日期:

let comp: DateComponents = Calendar.current.dateComponents([.year, .month], from: date)
let startOfMonth = Calendar.current.date(from: comp)!
print(dateFormatter.string(from: startOfMonth))

For end Date:

结束日期:

var comps2 = DateComponents()
comps2.month = 1
comps2.day = -1
let endOfMonth = Calendar.current.date(byAdding: comps2, to: startOfMonth)
print(dateFormatter.string(from: endOfMonth!))

#2

This is what I'm using. Pretty simple but it works.

这就是我用的。很简单，但很有效。

extension Calendar {

func dayOfWeek(_ date: Date) -> Int {
    var dayOfWeek = self.component(.weekday, from: date) + 1 - self.firstWeekday

    if dayOfWeek <= 0 {
        dayOfWeek += 7
    }

    return dayOfWeek
}

func startOfWeek(_ date: Date) -> Date {
    return self.date(byAdding: DateComponents(day: -self.dayOfWeek(date) + 1), to: date)!
}

func endOfWeek(_ date: Date) -> Date {
    return self.date(byAdding: DateComponents(day: 6), to: self.startOfWeek(date))!
}

func startOfMonth(_ date: Date) -> Date {
    return self.date(from: self.dateComponents([.year, .month], from: date))!
}

func endOfMonth(_ date: Date) -> Date {
    return self.date(byAdding: DateComponents(month: 1, day: -1), to: self.startOfMonth(date))!
}

func startOfQuarter(_ date: Date) -> Date {
    let quarter = (self.component(.month, from: date) - 1) / 3 + 1
    return self.date(from: DateComponents(year: self.component(.year, from: date), month: (quarter - 1) * 3 + 1))!
}

func endOfQuarter(_ date: Date) -> Date {
    return self.date(byAdding: DateComponents(month: 3, day: -1), to: self.startOfQuarter(date))!
}

func startOfYear(_ date: Date) -> Date {
    return self.date(from: self.dateComponents([.year], from: date))!
}

func endOfYear(_ date: Date) -> Date {
    return self.date(from: DateComponents(year: self.component(.year, from: date), month: 12, day: 31))!
}
}

#3

With Swift 3 & iOS 10 the easiest way I found to do this is Calendar's dateInterval(of:for:):

使用Swift 3和ios10，我发现最简单的方法是使用日历的日期间隔(of:for:):

guard let interval = calendar.dateInterval(of: .month, for: Date()) else { return }

Then use a date formatter to print the dates:

然后使用日期格式化程序打印日期:

let formatter = DateFormatter()
formatter.dateFormat = "dd-MM-yyyy"
let dateText = formatter.string(from: interval.start)

#4

This Extension Gives you expected output as per you want

这个扩展可以根据需要提供预期的输出

Here I return date

在这里,我返回日期

extension NSDate {
    func startOfMonth() -> NSDate? {
        guard
            let cal: NSCalendar = NSCalendar.currentCalendar(),
            let comp: NSDateComponents = cal.components([.Year, .Month], fromDate: self) else { return nil }
        comp.to12pm()
        let dateformattor = NSDateFormatter()
        dateformattor.dateFormat = "yyyy-MM-dd"
        dateformattor.timeZone = NSTimeZone.localTimeZone()
        let dt2 = dateformattor.stringFromDate(cal.dateFromComponents(comp)!)
        print(dt2)

        dateformattor.dateFormat = "yyyy-MM-dd"
        dateformattor.timeZone = NSTimeZone.init(abbreviation: "UTC")

        return dateformattor.dateFromString(dt2)
    }

    func endOfMonth() -> NSDate? {
        guard
            let cal: NSCalendar = NSCalendar.currentCalendar(),
            let comp: NSDateComponents = NSDateComponents() else { return nil }
        comp.month = 1
        comp.day = -1
        comp.to12pm()
        let dateformattor = NSDateFormatter()
        dateformattor.dateFormat = "yyyy-MM-dd"
        dateformattor.timeZone = NSTimeZone.localTimeZone()
        let dt2 = dateformattor.stringFromDate(cal.dateByAddingComponents(comp, toDate: self.startOfMonth()!, options: [])!)

        dateformattor.dateFormat = "yyyy-MM-dd"
        dateformattor.timeZone = NSTimeZone.init(abbreviation: "UTC")

        return dateformattor.dateFromString(dt2)
    }
}
internal extension NSDateComponents {
    func to12pm() {
        self.hour = 12
        self.minute = 0
        self.second = 0
    }
}

**OUTPUT :- **

* *输出:- * *

Start Date of Month :- 2016-12-01 00:00:00 +0000
End Date of Month :- 2016-12-31 00:00:00 +0000

#1