Laravel `array_pluck` on any key

You can use Laravel collections to achieve something like this.

$data = collect($array['users']);
$ids = $data->pluck('id');
return $ids;

From Laravel 5.7, you may use the Arr::pluck() helper.

use Illuminate\Support\Arr;

Arr::pluck($array['users'], 'id')

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Use array_pluck($array['users'], 'id')

The function only supports a single dimensional array. It will search for keys in the array which match the second parameter; which in your case is 'id'. You'll note that the array you're searching in your examples only has a key named users and none with the name id.

Using $array['users'] means pluck looks through that array and subsequently finds keys named id on each element.