Check if specific array key exists in multidimensional array - PHP

Question

I have a multidimensional array e.g. (this can be many levels deep):

$array = Array ( 
    [21] => Array ( ) 
    [24] => Array ( 
        [22] => A         


        

Answer 1

array_key_exists() is helpful.

Then something like this:

function multiKeyExists(array $arr, $key) {

    // is in base array?
    if (array_key_exists($key, $arr)) {
        return true;
    }

    // check arrays contained in this array
    foreach ($arr as $element) {
        if (is_array($element)) {
            if (multiKeyExists($element, $key)) {
                return true;
            }
        }

    }

    return false;
}

Working example: http://codepad.org/GU0qG5su