问题
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.
Thanks in Advance.
回答1:
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.
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2:
I solve the problem thanks for Support
Code :- it give the current week start and end date.
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3:
Here is Swift 3 Version:-
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 :
let startWeek = Date().startOfWeek
let endWeek = Date().endOfWeek
print(startWeek ?? "not found start date")
print(endWeek ?? "not found end date")
回答4:
A Swift version
of vikingosegundo's answer:
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5:
Here's an elegant way for Swift 3 (Xcode 8+):
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:
print(Date().startOfWeek)
print(Date().endOfWeek)
回答6:
First find the current date...
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.
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.
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
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.
NSDateComponents *componentsToAdd = [gregorian components:NSDayCalendarUnit fromDate:beginningOfWeek];
[componentsToAdd setDay:6];
NSDate *endOfWeek = [gregorian dateByAddingComponents:componentsToAdd toDate:beginningOfWeek options:0];
for next and previous ....
-(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7:
Here is a solution for the swift4, we can get all the days for the current week.
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: $0 - dayOfWeek, to: today) }
回答8:
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 setWeekday to 7 and you can get the prior week by subtracting 1 from [components week]
// 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9:
//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;
}
回答10:
Swift 4 Solution
I have figured out according to my requirement, where I have find out dates for following.
1. Today
2. Tomorrow
3. This Week
4. This Weekend
5. Next Week
6. Next Weekend
So, I have created Date Extension to get Dates of Current Week and Next Week.
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)
}
}
USAGE:
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
You can modify Extension according to your need.
Thanks!
回答11:
You can get current day and date by following code:
NSDate *today = [NSDate date];
NSDateFormatter *dateFormat = [[[NSDateFormatter alloc] init] autorelease];
[dateFormat setDateFormat:@"EEEE"];
NSString *weekDay = [dateFormat stringFromDate:today];
[dateFormat setDateFormat:@"dd"];
NSString *thedate=[dateFormat stringFromDate:today];
//[dateFormat release];
NSLog(@"%@ %@", weekDay,thedate);
Now, You need to put some logic in it to calculate starting date and end date of the week. The logic will be such kind,
if the week day is Monday
then
starting date = current date - 0
end date = current date + 6
and so on
I think you can get the idea of it.
回答12:
By take advantage of the method rangeOfUnit:startDate:interval:forDate: of NSDate, there is a simpler way to achieve this:
- (void)startDate:(NSDate **)start andEndDate:(NSDate **)end ofWeekOn:(NSDate *)date{
NSDate *startDate = nil;
NSTimeInterval duration = 0;
BOOL b = [[NSCalendar currentCalendar] rangeOfUnit:NSWeekCalendarUnit startDate:&startDate interval:&duration forDate:date];
if(! b){
*start = nil;
*end = nil;
return;
}
NSDate *endDate = [startDate dateByAddingTimeInterval:duration-1];
*start = startDate;
*end = endDate;
}
NSDate *this_start = nil, *this_end = nil;
[self startDate:&this_start andEndDate:&this_end ofWeekOn:[NSDate date]];
So now you have the start date and end date of this week. Then last week:
NSDate *lastWeekDate = [this_start dateByAddingTimeInterval:-10];
NSDate *last_start = nil, *last_end = nil;
[self startDate:&last_start andEndDate:&last_end ofWeekOn:lastWeekDate];
Next week:
NSDate *nextWeekDate = [this_end dateByAddingTimeInterval:10];
NSDate *next_start = nil, *next_end = nil;
[self startDate:&next_start andEndDate:&next_end ofWeekOn:nextWeekDate];
Now you have them all.
回答13:
Swift 3
First find the current date...
let today = Date()
let gregorian = Calendar(identifier: .gregorian)
var weekdayComponents: DateComponents? = gregorian.dateComponents([.weekday], from: today)
Sunday = 1, Monday = 2, Tuesday = 3, Wednesday = 4, Thursday = 5, Friday = 6 and Saturday = 7.
var componentsToSubtract = DateComponents()
componentsToSubtract.day = (0 - (weekdayComponents?.weekday!)!) + 2
beginningOfWeek = gregorian.date(byAdding: componentsToSubtract, to: today)
var componentsToAdd: DateComponents? = gregorian.dateComponents([.day], from: beginningOfWeek!)
componentsToAdd?.day = 6
endOfWeek = gregorian.date(byAdding: componentsToAdd!, to: beginningOfWeek!)
let components: DateComponents? = gregorian.dateComponents([.month], from: beginningOfWeek!)
let month: Int? = components?.month
let components1: DateComponents? = gregorian.dateComponents([.month], from: endOfWeek!)
let month1: Int? = components1?.month
print("\(month) - \(month1)")
showDate(start:beginningOfWeek!, end:endOfWeek!, strtMn:month!, endMn:month1!)
func showDate(start:Date, end:Date, strtMn:Int, endMn:Int) {
if strtMn == endMn{
let formatter = DateFormatter()
formatter.dateFormat = "MMM dd"
let stringFromDate: String = formatter.string(from: start)
let formatter1 = DateFormatter()
formatter1.dateFormat = "dd"
let stringFromDate1: String = formatter1.string(from: end)
print("\(stringFromDate) - \(stringFromDate1)")
lblDate.text = "\(stringFromDate) - \(stringFromDate1)"
}
else{
let formatter = DateFormatter()
formatter.dateFormat = "MMM dd"
let stringFromDate: String = formatter.string(from: start)
let formatter1 = DateFormatter()
formatter1.dateFormat = "MMM dd"
let stringFromDate1: String = formatter1.string(from: end)
print("\(stringFromDate) - \(stringFromDate1)")
lblDate.text = "\(stringFromDate) - \(stringFromDate1)"
}
}
for next and previous ....
@IBAction func week_CalendarActionEvents(_ sender: UIButton) {
let gregorian = Calendar(identifier: .gregorian)
var offsetComponents = DateComponents()
var nextStrtDate: Date?
var nextEndDate: Date?
var startDate: Date?
var endDate: Date?
startDate = beginningOfWeek
endDate = endOfWeek
if sender.tag == 1 {
offsetComponents.day = -7
}
else if sender.tag == 2 {
offsetComponents.day = 7
}
nextStrtDate = gregorian.date(byAdding: offsetComponents, to:startDate!)
startDate = nextStrtDate
beginningOfWeek = startDate
nextEndDate = gregorian.date(byAdding: offsetComponents, to: endDate!)
endDate = nextEndDate
endOfWeek = endDate
let components: DateComponents? = gregorian.dateComponents([.month], from: startDate!)
let month: Int? = components?.month
let components1: DateComponents? = gregorian.dateComponents([.month], from: endDate!)
let month1: Int? = components1?.month
print("\(month)- \(month1)")
showDate(start:startDate!, end:endDate!, strtMn:month!, endMn:month1!)
}
回答14:
Swift 3+: Simple solution with extension
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)
}
var yesterdayDate: Date? {
return NSCalendar.current.date(byAdding: .day, value: -1, to: noon)!
}
var tommorowDate: Date? {
return NSCalendar.current.date(byAdding: .day, value: 1, to: noon)!
}
var previousDate: Date? {
let oneDay:Double = 60 * 60 * 24
return self.addingTimeInterval(-(Double(oneDay)))
}
var nextDate: Date? {
let oneDay:Double = 60 * 60 * 24
return self.addingTimeInterval(oneDay)
}
var noon: Date {
return NSCalendar.current.date(bySettingHour: 12, minute: 0, second: 0, of: self)!
}
var month: Int {
return Calendar.current.component(.month, from: self)
}
}
回答15:
Swift 4.2
If you want to show the current week dates, here is the code.
override func viewDidLoad() {
super.viewDidLoad()
for dateIndex in 0..<7 {
guard let startWeek = Date().startOfWeek else { return }
let date = Calendar.current.date(byAdding: .day, value: dateIndex + 1, to: startWeek)
print(date)
}
}
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)
}
}
回答16:
In swift 3.0
let cal = NSCalendar.current
//weekday
let weekday = cal.component(.weekday, from: Date())
var dateComp = cal.dateComponents([.hour, .minute, .second, .day, .month, .year], from: Date())
print(dateComp.day!)
//Start Date of the week - Sunday
dateComp.day = dateComp.day! - (weekday - 1)// start date of week
print(cal.date(from: dateComp)!)
//End Date of the Week - Saturday
dateComp = cal.dateComponents([.hour, .minute, .second, .day, .month, .year], from: Date())
dateComp.day = dateComp.day! + (7 - weekday)
print(cal.date(from: dateComp)!)
来源：https://stackoverflow.com/questions/11681815/current-week-start-and-end-date