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iphone - How do I calculate the number of days in this year in Objective C

How can i calculate the number of days in a year for any calendar, not just gregorian. I have tried this

NSUInteger *days = [[NSCalendar currentCalendar] rangeOfUnit:NSDayCalendarUnit inUnit:NSYearCalendarUnit forDate:[NSDate date]];

but that gives me the number of days in the current month instead of the number of days in the current year.

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I finally came up with a solution that works. What I do is first calculate the number of months in the year and then for each month calculate the number of days for that month.

The code looks like this:

NSUInteger days = 0;
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDate *today = [NSDate date];
NSDateComponents *components = [calendar components:NSYearCalendarUnit fromDate:today];
NSUInteger months = [calendar rangeOfUnit:NSMonthCalendarUnit
                                   inUnit:NSYearCalendarUnit
                                  forDate:today].length;
for (int i = 1; i <= months; i++) {
    components.month = i;
    NSDate *month = [calendar dateFromComponents:components];
    days += [calendar rangeOfUnit:NSDayCalendarUnit
                           inUnit:NSMonthCalendarUnit
                          forDate:month].length;
}

return days;

It is not as neat as I would have hoped for but it will work for any calendar such as the ordinary gregorian one or the islamic one.


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