NSCalendar NSDateComponents weekofYear return 1 with date 2014-12-31

Question

I want to get weekofYear with date \'2014-12-31\' ,but it always return 1 not 52 here is my code:

NSCalendar *calendar = [NSCalendar currentCalendar];
NSUIntege         


        

Answer 1

Set the minimumDaysInFirstWeek property of the NSCalendar instance before obtaining the date components.

NSCalendar *calendar = [NSCalendar currentCalendar];
calendar.minimumDaysInFirstWeek = 7; // the week has to be completely within one year

NSUInteger unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit | NSWeekdayCalendarUnit | NSWeekOfMonthCalendarUnit | NSWeekOfYearCalendarUnit;
NSDateComponents *dateComponent = [calendar components:unitFlags fromDate:[NSDate date]];

NSLog(@"%i",dateComponent.weekOfYear); // 52