Kobski Kobski - 11 months ago 38
Objective-C Question

Detecting if NSDate contains a weekend day

I have this category added to NSDate:

- (bool)isWeekend
NSString* s = [self asString:@"e"];

if ([s isEqual:@"6"])
return YES;
else if ([s isEqual:@"7"])
return YES;
return NO;

Helper function:

- (NSString*)asString:(NSString*)format
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:format];
NSString *formattedDateString = [dateFormatter stringFromDate:self];
[dateFormatter release];

return formattedDateString;

should return YES if it is a saturday or a sunday. But it does not work if the locale has a week start on a sunday, in which case friday will be day 6 and saturday will be day 7.

How can I solve this?


You want to use NSCalendar and NSDateComponents:

NSDate *aDate = [NSDate date];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSRange weekdayRange = [calendar maximumRangeOfUnit:NSWeekdayCalendarUnit];
NSDateComponents *components = [calendar components:NSWeekdayCalendarUnit fromDate:aDate];
NSUInteger weekdayOfDate = [components weekday];

if (weekdayOfDate == weekdayRange.location || weekdayOfDate == weekdayRange.length) {
  //the date falls somewhere on the first or last days of the week

This is operating under the assumption that the first and last days of the week comprise the "week ends" (which is true for the Gregorian calendar. It may not be true in other calendars).