How can I make array of array to just simple associative array by swapping the keys?

Question

How can I make a multidimensional array like the first key becomes the root key and the second key becomes the value?

Is there any build in function for this, if yes then which one?

My Input array is:

Array
(
    [key1] => Array
        (
            [key] => key1
            [label] => value1
        )

    [key2] => Array
        (
            [key] => key2
            [label] => value2
        )

    [key3] => Array
        (
            [key] => key3
            [label] => value3
        )

    [key4] => Array
        (
            [key] => key4
            [label] => value4
        )

)

Expected Output:

Array (
    [key1] => value1

    [key2] => value2

    [key3] => value3

    [key4] => value4

)

I can do it with iterating the for loop on array, but just looking for any existing function(s)!

Rarst · Accepted Answer · 2019-02-25 09:37:14Z

2

You can, indeed, do this without a loop with some native functions.

On top of my head:

$combined = array_combine( array_keys( $input ), array_column( $input, 'label' ) );

Or if you want to take key from the item:

$combined = array_column( $input, 'label', 'key' );

answered Feb 25, 2019 at 9:37

Rarst

2,39516 silver badges26 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

VBMali Over a year ago

Second one also worked for me, which one is better? for sure second option still want your thoughts...

Rarst Over a year ago

It depends where you want keys to come from, to preserve keys from original array or to take some value from every item as a key to use. For your given example data these two should be the same (since keys of the array are the same as key values in items).

Rahul · Accepted Answer · 2019-02-25 09:36:17Z

1

You can try out this combination of core array functions,

$input = array_combine(array_keys($input), array_column($input, 'label'));

array_combine — Creates an array by using one array for keys and another for its values
array_keys — Return all the keys or a subset of the keys of an array
array_column — Return the values from a single column in the input array

answered Feb 25, 2019 at 9:36

Rahul

18.6k7 gold badges43 silver badges64 bronze badges

Comments

Eriks Klotins · Accepted Answer · 2019-02-25 09:37:04Z

1

You can try array_reduce:

$array = // .. your array
$result = array_reduce($array, function($carry, $item){
    $carry[$item->key] = $item->value;
    return $carry;
},[]);

answered Feb 25, 2019 at 9:37

Eriks Klotins

4,1701 gold badge14 silver badges27 bronze badges

Collectives™ on Stack Overflow

How can I make array of array to just simple associative array by swapping the keys?

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related