For some reason, Apple didn’t provide an easy way to extract day, month and year from an NSDate. Probably because they think OS X shouldn’t be Western-centric and presume a Gregorian calendar (although they could have simply extracted this data from current locale). Here is a simple category that allows just that.

// NSDate+IVDateComponents.h

#import 

@interface NSDate (IVDateComponents)

@property (nonatomic, readonly) NSInteger year;
@property (nonatomic, readonly) NSInteger month;
@property (nonatomic, readonly) NSInteger day;
@end

// NSDate+IVDateComponents.m

#import "NSDate+IVDateComponents.h"


@implementation NSDate (IVDateComponents)
-(NSInteger)year
{
	unsigned units = NSYearCalendarUnit;
	NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
	NSDateComponents *components = [calendar components:units fromDate:self];
	
	return [components year];
}
-(NSInteger)month
{
	unsigned units = NSMonthCalendarUnit;
	NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
	NSDateComponents *components = [calendar components:units fromDate:self];
	
	return [components month];
}
-(NSInteger)day
{
	unsigned units = NSDayCalendarUnit;
	NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
	NSDateComponents *components = [calendar components:units fromDate:self];
	
	return [components day];
}
@end

Note that this code is very Western-centric and always presumes the Gregorian calendar. Sue me.

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via blog.vucica.net