ios 当前周开始和结束日期

Current Week Start and End Date

提问by Rushabh

I want to get the current week start and end date and I also want to use the previous week start and end date and next week of the start and end date in current month.

我想获取当前周的开始和结束日期，我还想使用当月开始和结束日期的前一周开始和结束日期以及下周的开始和结束日期。

Thanks in Advance.

提前致谢。

采纳答案by Rushabh

I solve the problem thanks for Support

我解决了问题谢谢支持

Code :- it give the current week start and end date.

代码：- 它给出了当前周的开始和结束日期。

 NSDate *today = [NSDate date];
 NSLog(@"Today date is %@",today);
 dateFormat = [[NSDateFormatter alloc] init];
 [dateFormat setDateFormat:@"yyyy-MM-dd"];// you can use your format.

 //Week Start Date 

 NSCalendar *gregorian = [[NSCalendar alloc]        initWithCalendarIdentifier:NSGregorianCalendar];

NSDateComponents *components = [gregorian components:NSWeekdayCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit fromDate:today];

int dayofweek = [[[NSCalendar currentCalendar] components:NSWeekdayCalendarUnit fromDate:today] weekday];// this will give you current day of week

[components setDay:([components day] - ((dayofweek) - 2))];// for beginning of the week.

NSDate *beginningOfWeek = [gregorian dateFromComponents:components];
NSDateFormatter *dateFormat_first = [[NSDateFormatter alloc] init];
[dateFormat_first setDateFormat:@"yyyy-MM-dd"];
dateString2Prev = [dateFormat stringFromDate:beginningOfWeek];

weekstartPrev = [[dateFormat_first dateFromString:dateString2Prev] retain];

NSLog(@"%@",weekstartPrev);


//Week End Date

 NSCalendar *gregorianEnd = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

 NSDateComponents *componentsEnd = [gregorianEnd components:NSWeekdayCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit fromDate:today];

 int Enddayofweek = [[[NSCalendar currentCalendar] components:NSWeekdayCalendarUnit fromDate:today] weekday];// this will give you current day of week

 [componentsEnd setDay:([componentsEnd day]+(7-Enddayofweek)+1)];// for end day of the week

 NSDate *EndOfWeek = [gregorianEnd dateFromComponents:componentsEnd];
 NSDateFormatter *dateFormat_End = [[NSDateFormatter alloc] init];
 [dateFormat_End setDateFormat:@"yyyy-MM-dd"];
 dateEndPrev = [dateFormat stringFromDate:EndOfWeek];

 weekEndPrev = [[dateFormat_End dateFromString:dateEndPrev] retain];
  NSLog(@"%@",weekEndPrev);

回答by vikingosegundo

rangeOfUnit:startDate:interval:forDate:. It gives you the start and the interval for a certain time unit. With it it is easy to find the start of the week in the used calendar and add the range-1 to get the latest second in that week.

rangeOfUnit:startDate:interval:forDate:. 它为您提供特定时间单位的开始和间隔。使用它可以很容易地在使用的日历中找到一周的开始，并添加 range-1 以获取该周的最新秒数。

NSCalendar *cal = [NSCalendar currentCalendar];
NSDate *now = [NSDate date];
NSDate *startOfTheWeek;
NSDate *endOfWeek;
NSTimeInterval interval;
[cal rangeOfUnit:NSWeekCalendarUnit 
       startDate:&startOfTheWeek 
        interval:&interval 
         forDate:now];
//startOfWeek holds now the first day of the week, according to locale (monday vs. sunday)

endOfWeek = [startOfTheWeek dateByAddingTimeInterval:interval-1];
// holds 23:59:59 of last day in week.

回答by Mandeep Singh

Here is Swift 3 Version:-

这是 Swift 3 版本：-

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)
    }

    var endOfWeek: 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: 7, to: sunday)
    }
}

You can get the week start date and end date like this :

您可以像这样获取周开始日期和结束日期：

let startWeek = Date().startOfWeek
let endWeek = Date().endOfWeek

print(startWeek ?? "not found start date")
print(endWeek ?? "not found end date") 

回答by SoftDesigner

A Swift version

一个 Swift 版本

of vikingosegundo's answer:

的vikingosegundo的回答：

let calendar = NSCalendar.currentCalendar()
var startOfTheWeek: NSDate?
var endOfWeek: NSDate!
var interval = NSTimeInterval(0)

calendar.rangeOfUnit(.WeekOfMonth, startDate: &startOfTheWeek, interval: &interval, forDate: NSDate())
endOfWeek = startOfTheWeek!.dateByAddingTimeInterval(interval - 1)

回答by elquimista

Here's an elegant way for Swift 3 (Xcode 8+):

这是 Swift 3 (Xcode 8+) 的优雅方式：

extension Date {
    var startOfWeek: Date {
        let date = Calendar.current.date(from: Calendar.current.dateComponents([.yearForWeekOfYear, .weekOfYear], from: self))!
        let dslTimeOffset = NSTimeZone.local.daylightSavingTimeOffset(for: date)
        return date.addingTimeInterval(dslTimeOffset)
    }

    var endOfWeek: Date {
        return Calendar.current.date(byAdding: .second, value: 604799, to: self.startOfWeek)!
    }
}

And we can use this extension like this:

我们可以像这样使用这个扩展：

print(Date().startOfWeek)
print(Date().endOfWeek)

回答by Vikas S Singh

First find the current date...

首先找到当前日期...

NSDate *today = [NSDate date];
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *weekdayComponents     = [gregorian components:NSWeekdayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit fromDate:today];

Calcuate number of days to substract from today, in order to get the first day of the week. In this case, the first day of the week is monday. This is represented by first subtracting 0 with the weekday integer followed by adding 2 to the setDay.

计算从今天减去的天数，以获得一周的第一天。在这种情况下，一周的第一天是星期一。这通过首先用工作日整数减去 0 然后将 2 添加到 setDay 来表示。

Sunday = 1, Monday = 2, Tuesday = 3, Wednesday = 4, Thursday = 5, Friday = 6 and Saturday = 7. By adding more to this integers, you will go into the next week.

星期日 = 1，星期一 = 2，星期二 = 3，星期三 = 4，星期四 = 5，星期五 = 6 和星期六 = 7。通过增加这些整数，你将进入下一周。

NSDateComponents *componentsToSubtract  = [[NSDateComponents alloc] init];
[componentsToSubtract setDay: (0 - [weekdayComponents weekday]) + 2];   
[componentsToSubtract setHour: 0 - [weekdayComponents hour]];
[componentsToSubtract setMinute: 0 - [weekdayComponents minute]];
[componentsToSubtract setSecond: 0 - [weekdayComponents second]];

Create date for first day in week

为一周的第一天创建日期

NSDate *beginningOfWeek = [gregorian dateByAddingComponents:componentsToSubtract toDate:today options:0];

By adding 6 to the date of the first day, we can get the last day, in our example Sunday.

通过将第一天的日期加上 6，我们可以得到最后一天，在我们的示例中为星期日。

NSDateComponents *componentsToAdd = [gregorian components:NSDayCalendarUnit fromDate:beginningOfWeek];
[componentsToAdd setDay:6];
NSDate *endOfWeek = [gregorian dateByAddingComponents:componentsToAdd toDate:beginningOfWeek options:0];

for next and previous ....

对于下一个和上一个....

-(IBAction)Week_CalendarActionEvents:(id)sender{

    NSCalendar *gregorian = [[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar] autorelease];
    NSDateComponents *offsetComponents = [[[NSDateComponents alloc] init] autorelease];
    NSDate *nextDate;

    if(sender==Week_prevBarBtn)  // Previous button events 
        [offsetComponents setDay:-7];
    else if(sender==Week_nextBarBtn) // next button events 
        [offsetComponents setDay:7];

    nextDate = [gregorian dateByAddingComponents:offsetComponents toDate:selectedDate options:0];

    selectedDate = nextDate;
    [selectedDate retain];

    NSDateComponents *components = [gregorian components:NSWeekCalendarUnit fromDate:selectedDate];
    NSInteger week = [components week];
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"MMMM YYYY"];
    NSString *stringFromDate = [formatter stringFromDate:selectedDate];
    [formatter release];
    [Week_weekBarBtn setTitle:[NSString stringWithFormat:@"%@,Week %d",stringFromDate,week]];
}

回答by PrafulD

Here is a solution for the swift4, we can get all the days for the current week.

这是 swift4 的解决方案，我们可以获得当前一周的所有天数。

var calendar = Calendar(identifier: Calendar.Identifier.gregorian)
let today = calendar.startOfDay(for: Date())    
let dayOfWeek = calendar.component(.weekday, from: today) - calendar.firstWeekday
let weekdays = calendar.range(of: .weekday, in: .weekOfYear, for: today)!
let days = (weekdays.lowerBound ..< weekdays.upperBound)
                    .flatMap { calendar.date(byAdding: .day, value: 
1. Today

2. Tomorrow 

3. This Week 

4. This Weekend 

5. Next Week 

6. Next Weekend
 - dayOfWeek, to: today) }

回答by Rashesh Bosamiya

Swift 4 Solution

Swift 4 解决方案

I have figured out according to my requirement, where I have find out dates for following.

我已经根据我的要求找到了，我在那里找到了以下日期。

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)
    }
}

So, I have created Date Extensionto get Dates of Current Weekand Next Week.

所以，我创建Date Extension了获取Current Week和Next Week 的日期。

CODE

代码

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

USAGE:

用法：

//Begining of Week Date

- (NSDate*) beginingOfWeekOfDate{

    NSCalendar *tmpCalendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [tmpCalendar components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitWeekOfYear|NSCalendarUnitWeekday fromDate:self];//get the required calendar units

    NSInteger weekday = tmpCalendar.firstWeekday;  
    components.weekday = weekday; //weekday
    components.hour = 0;
    components.minute = 0;
    components.second = 0;

    NSDate *fireDate = [tmpCalendar dateFromComponents:components];

    return fireDate;
}

//End of Week Date

-(NSDate *)endOfWeekFromDate{

    NSCalendar *tmpCalendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [tmpCalendar components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitWeekOfYear|NSCalendarUnitWeekday fromDate:self];//get the required calendar units

    int weekday = 7; //Saturday
    if (tmpCalendar.firstWeekday != 1) {
        weekday = 1;
    }
    components.weekday = weekday;//weekday
    components.hour = 23;
    components.minute = 59;
    components.second = 59;

    NSDate *fireDate = [tmpCalendar dateFromComponents:components];

    return fireDate;
}

You can modify Extensionaccording to your need.

您可以Extension根据自己的需要进行修改。

Thanks!

谢谢！

回答by Sargis Gevorgyan

// Finds the date for the first day of the week
- (NSDate *)getFirstDayOfTheWeekFromDate:(NSDate *)givenDate
{
    NSCalendar *calendar = [NSCalendar currentCalendar];

    // Edge case where beginning of week starts in the prior month
    NSDateComponents *edgeCase = [[NSDateComponents alloc] init];
    [edgeCase setMonth:2];
    [edgeCase setDay:1];
    [edgeCase setYear:2013];
    NSDate *edgeCaseDate = [calendar dateFromComponents:edgeCase];

    NSDateComponents *components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:edgeCaseDate];
    [components setWeekday:1]; // 1 == Sunday, 7 == Saturday
    [components setWeek:[components week]];

    NSLog(@"Edge case date is %@ and beginning of that week is %@", edgeCaseDate , [calendar dateFromComponents:components]);

    // Find Sunday for the given date
    components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:givenDate];
    [components setWeekday:1]; // 1 == Sunday, 7 == Saturday
    [components setWeek:[components week]];

    NSLog(@"Original date is %@ and beginning of week is %@", givenDate , [calendar dateFromComponents:components]);

    return [calendar dateFromComponents:components];
}

回答by iwasrobbed

Here's some code and it also checks an edge case where the beginning of the week starts in the prior month. You can get end of week by setting setWeekdayto 7and you can get the prior week by subtracting 1from [components week]

这是一些代码，它还检查一周的开始在上个月开始的边缘情况。您可以通过设置让周结束setWeekday至7，你可以通过减去得到的前一周1，从[components week]

##代码##