PHP multidimensional array search by value

Question

I have an array where I want to search the uid and get the key of the array.

Examples

Assume we have the following 2-dimensional array:

<

Answer 1

$a = ['x' => ['eee', 'ccc'], 'b' => ['zzz']];

$found = null;
$search = 'eee';

array_walk($a, function ($k, $v) use ($search, &$found) {
    if (in_array($search, $k)) {
        $found = $v;
    }
});

var_dump($found);