Retrieve an object within an NSArray / NSDictionary heirarchy based on other objects within it.

Question

Sorry about the weird title... all will be explained.

Basically I have an array/dictionary structure like this in my app:

NSArray {

    NSDictionary {
        (NSString *)id;
        (NSDictionary *)dictionary;
    }

    NSDictionary {
        (NSString *)id;
        (NSDictionary *)dictionary;
    }

    NSDictionary {
        (NSString *)id;
        (NSDictionary *)dictionary;
    }

    etc...

}

Hope that's easy to work out...

Now I have an (NSString *)id and I want to get the (NSDictionary *)dictionary which corresponds to it.

Is there any way that I can do this?

Thank you

Tom

Answer 1

Try something like this

for (NSDictionary *dict in dictArray) {
    if ([[dict objectForKey:@"id"] isEqualToString:targetID]){
        return [dict objectForKey:@"dictionary"];
    }
}

I have not compiled the code(don't have mac near me), but I think you got the idea. The basic idea is to loop through the array and compare query string. But if you have many items then this linear search might be time consuming.

Answer 2

If the ids are unique, I'd use NSDictionary as my top level object instead of the NSArray. That way you can just do: [dict objectForKey:stringID]

NSArray doesn't really make sense here unless you are using it as a tables datasource.