iPhone - How to build a list of unique items

Question

I want an array which contains only unique items. I know I could do this with an NSDictionary adding items with keys and then get allKeys. This would ensure that the NSArray contains only unique items, but I feel that this would be overkill and believe that there should be an easier way to do this, but cannot find one.

Answer 1

You can use NSSet for this

Answer 2

Use NSSet or NSMutableSet for this. Keep in mind that uniqueness will be based on object address if you don't override the isEqual: method. Unless, of course, you are using classes that implement that method (NSNumber, NSValue, for example).

Answer 3

NSArray* uniqueArray = [[NSSet setWithArray:originalArray] allObjects];

Uniqueness is based on the isEqual: method.