calculer la semaine civile

Question

comment puis-je calculer la semaine calendaire? Un an a 52/53 semaines et il y a deux règles:

-USA

-DIN 1355/ISO 8601

Je voudrais travailler avec DIN 1355/ISO 8601. Comment puis-je gérer cette?

Modifier:

NSDate *today = [NSDate date]; 
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init]; 
[dateFormat setDateFormat:@"ww"]; 
NSString *weeknumber = [dateFormat stringFromDate: today]; 
NSLog(@"week: %@", weeknumber); 

Tiré de http://iosdevelopertips.com/cocoa/date-formatter-examples.html

Où puis-je trouver les formats de date autorisés?

Answer 1

Utilisez un NSCalendar et NSDateComponents.

NSCalendar *cal = [NSCalendar currentCalendar]; 
NSDateComponents *components = [cal components:NSWeekCalendarUnit fromDate:date]; 
NSInteger week = [components week]; 

Answer 2

Vous devez utilisateur NSDateFormatter comme ceci:

NSDateFormatter *fm = [[NSDateFormatter alloc] initWithDateFormat:@"ww" allowNaturalLanguage:NO]; 
NSString *week = [fm stringFromDate: date]; 

Answer 3

Ou utilisez:

CFAbsoluteTime currentTime = CFAbsoluteTimeGetCurrent(); 
CFTimeZoneRef currentTimeZone = CFTimeZoneCopyDefault();  
SInt32 weekNumber = CFAbsoluteTimeGetWeekOfYear(currentTime, currentTimeZone); 

La numérotation suit la définition ISO 8601 de la semaine.

Answer 4

NSDate *today = [NSDate date]; 
NSCalendar *ISO8601 = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierISO8601]; 
ISO8601.firstWeekday = 2; // Sunday = 1, Saturday = 7 
ISO8601.minimumDaysInFirstWeek = 4; 
NSDateComponents *components = [ISO8601 components:NSCalendarUnitWeekOfYear fromDate:today]; 
NSUInteger weekOfYear = [components weekOfYear]; 
NSDate *mondaysDate = nil; 
[ISO8601 rangeOfUnit:NSCalendarUnitYearForWeekOfYear startDate:&mondaysDate interval:NULL forDate:today]; 
NSLog(@"The current Weeknumber of Year %ld ", weekOfYear); 

Answer 5

Il existe plusieurs types de Canlendar.

Week number according to the ISO-8601 standard, weeks starting on Monday. The first week of the year is the week that contains that year's first Thursday (='First 4-day week'). The highest week number in a year is either 52 or 53. This year has 52 weeks.This is not the only week numbering system in the world, other systems use weeks starting on Sunday (US) or Saturday (Islamic). 

Plus de détails: http://www.epochconverter.com/weeknumbers

et Apple ne supporte que, pour que vous puissiez trouver correctement aiguillés par https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSCalendar_Class/

Par exemple, avec ISO-8601 standard:

NSCalendar *ISO8601 = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierISO8601]; 

Hope this pourrait Aidez-moi.