NSDictionary keys with @ symbol

Question

Like asked here before Using valueForKeyPath on NSDictionary if a key starts the @ symbol?

If i have to use NSDictionary with keys like "@ID" and "@Name" (Server side limitations,I have no control over the naming) how can i work around that? Right now the app just crash every time I'm trying to access to this kind of keys.

I'm not totally sure what you're doing, can you show the code where the problem is occurring? — Ander, Jul 16 '13 at 07:20

score 0 · Accepted Answer · answered Jul 16 '13 at 07:21

0

As already stated you cannot do this. To Paraphrase Apple Docs reg. Key format -

Keys must use ASCII encoding, begin with a lowercase letter, and may not contain whitespace.

So trying to have a key with @.. as start isn't going to cut it. What I suggest you do is this - since you cannot change the way your backend sends the keys, you can control how those keys are represented in iOS. So Once you get the keys remove the starting @ symbol and insert the rest of the string as key. Since @ is constant across all keys, removing them from all keys should not affect cardinality of your dict.

answered Jul 16 '13 at 07:21

Srikar Appalaraju

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Thans, but how can i remove it when i cannot access this keys? when i print [MyDict allKeys] the app crashes too. – ItayAmza Jul 16 '13 at 07:31
1

before populating `MyDict` process your keys which you got from your server and then populate `MyDict` with the new keys... Is that clear? – Srikar Appalaraju Jul 16 '13 at 07:36
Yes I'll do that, Thanks. – ItayAmza Jul 16 '13 at 07:39
@ItayAmza, I think there is way to handle the situation at your side. check my answer, please. – holex Jul 16 '13 at 07:44
I also experienced this issue when @ was used in the beginning of the key - not in the middle or end. The obvious solution was to use a string replace on '@' to e.g. '(a)'. When I tried to break it again with other "odd" characters, numbers, uppercase or lower, I failed. – kjoelbro Apr 09 '15 at 09:32

score 0 · Answer 2 · answered Jul 16 '13 at 07:42

what if you try to convert the dictionary after you get it with the irregular keys?

the idea would be this, and yes, it is thread-safe:

NSDictionary *_dictionary = [NSDictionary dictionaryWithObjectsAndKeys:@"value", @"@ID", @"value2", @"@Name", nil];

NSMutableDictionary *_mutableDictionary = [NSMutableDictionary dictionary];
NSLock *_lock = [[NSLock alloc] init];
[_dictionary enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
    if ([_lock tryLock]) {
        NSString *_newKey = [key stringByReplacingOccurrencesOfString:@"@" withString:@""];
        [_mutableDictionary setValue:obj forKey:_newKey];
        [_lock unlock];
    }
}];

NSLog(@"ID : %@", [_mutableDictionary valueForKey:@"ID"]);
NSLog(@"Name : %@", [_mutableDictionary valueForKey:@"Name"]);

@ItayAmza, anytime, if you think it is useful, please don't forget to mark it. :) — holex, Jul 16 '13 at 07:58
I dont have enough reputation yet to vote and i did accepted @Srikar Appal answer, Sorry. — ItayAmza, Jul 16 '13 at 08:12

NSDictionary keys with @ symbol

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