Question

In my application, I’m having NSArray that holds objects of NSDictionary.
In each dictionary, there’s one “Primary” that holds value of type NSNumber which stores “YES” or “NO” (boolean value). And only dictionary object in the array can have the value “YES”.
Without using loops how can I get the dictionary object where the “Primary” key is YES?

Answer 1

You can call a convenience method on NSArray to find the object, but be aware, that such a method still uses a loop internally to find the object.

NSUInteger indexOfPrimary = [array indexOfObjectPassingTest:^(id obj, NSUInteger idx, BOOL *stop) {
    return [[obj objectForKey:@"Primary"] boolValue];
}];
NSDictionary *primary = nil;
if (indexOfPrimary != NSNotFound) {
    primary = [array objectAtIndex:indexOfPrimary];
}

Another option would be -[NSArray filteredArrayUsingPredicate:].