Question

I have an NSMutableArray that looks like this

 {
    "@active" = false;
    "@name" = NAME1;
 },
 {
    "@active" = false;
    "@name" = NAME2;
 }

Is there a way to convert this to an NSDictionary and then use objectForKey to get an array of the name objects? How else can I get these objects?

Answer 1

There is a even shorter form then this proposed by Hubert

NSArray *allNames = [array valueForKey:@"name"];

valueForKey: on NSArray returns a new array by sending valueForKey:givenKey to all it elements.

From the docs:

valueForKey:
Returns an array containing the results of invoking
valueForKey: using key on each of the array’s objects.

- (id)valueForKey:(NSString *)key

Parameters
key The key to retrieve.

Return Value
The value of the retrieved key.

Discussion
The returned array contains NSNull elements for each object that returns nil.

Example:

NSArray *array = @[@{ @"active": @NO,@"name": @"Alice"},
                   @{ @"active": @NO,@"name": @"Bob"}];

NSLog(@"%@\n%@", array, [array valueForKey:@"name"]);

result:

(
        {
        active = 0;
        name = Alice;
    },
        {
        active = 0;
        name = Bob;
    }
)
(
    Alice,
    Bob
)