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kavanseggie
7,565 PointsIs count not a property of the NSArray class and should therefore be referenced as quizArray.count?
Is count not a property of the NSArray class and should therefore be referenced as quizArray.count, rather than through the method [quizScore count]?
I checked Apple's docs and found: "Methods to Override... Any subclass of NSArray must override the primitive instance methods count and objectAtIndex:." What does this mean?
2 Answers
Zachary Betz
10,413 PointsTo answer your first question, count is not a property of NSArray so it cannot be referenced as quizArray.count. Instead, it is a method, so it must be referenced as [quizArray count].
To answer your second question, any subclass of NSArray must override the count and objectAtIndex methods.
I imagine there are scenarios where subclassing NSArray would be needed -- but most of the time just using the NSArray class will be sufficient.
Hope that helps :)
kavanseggie
7,565 PointsThanks Zachary. It makes sense that count is a method rather than a property, but in the Apple NSArray docs it says that it is in fact a property.
@property(readonly) NSUInteger count
Any idea what is going on here?
Zachary Betz
10,413 PointsOops, you're right kavanseggie. After a bit more research, turns out it's a matter of preference whether to use quizArray.count or [quizArray count].
Check out this Stack Overflow article for a more detailed explanation.