Question

I’m going crazy right now. I have a NSMutableArray with a bunch of Person objects. I want to remove the duplicated objects but it won’t work. This is what i got:

NSMutableArray *withoutDoubles =[[NSMutableArray alloc]init];
    NSArray *temp = [[NSArray alloc] initWithArray:tempResults];
    for (Person *person in temp) {
        if(![withoutDoubles containsObject:person]) {
            [withoutDoubles addObject:person];
        }       
    }
    for (Person *person in withoutDoubles) {
         NSLog(@"----> %@",person.name);
    }

That is not working, i still got duplicates. I also tried:

NSArray *temp = [[NSArray alloc] initWithArray:tempResults];
NSSet *set = [NSSet setWithArray:temp];

But it didn’t work either. I need some help here.

Thanks in advance.

Answer 1

If your definition of a duplicate is two separate Person objects whose properties are set the same then the best way to achieve this is to override these two methods in your Person object

- (BOOL)isEqual:(id)anObject
- (NSUInteger)hash

which will allow you to properly achieve the compare.

You would then need to do the following

for (Person *personToTest in temp) {
    BOOL duplicate = NO;
    for (Person *person in withoutDoubles) {
        if ([personToTest isEqual:person]) {
            duplicate = YES;
            break;
        }
    }
    if (!duplicate) {
        [withoutDoubles addObject:personToTest];
    }      
}