Dynamically accessing multidimensional array value

Question

I\'m trying to find (or create) a function. I have a multidimensional array:

$data_arr = [
    \"a\" => [
        \"aa\" => \"abfoo\",
        \"ab\"          


        

Answer 1

You can use this function that avoids the copy of the whole array (using references), is able to return a NULL value (using array_key_exists instead of isset), and that throws an exception when the path doesn't exist:

function getItem(&$array, $path) {
    $target = &$array;
    foreach($path as $key) {
        if (array_key_exists($key, $target))
            $target = &$target[$key];
        else throw new Exception('Undefined path: ["' . implode('","', $path) . '"]');
    }
    return $target;
}

demo:

$data = [
    "a" => [
        "aa" => "abfoo",
        "ab" => [
            "aba" => "abafoo",
            "abb" => NULL,
            "abc" => false
        ]
    ]
];

var_dump(getItem($data, ['a', 'ab', 'aba']));
# string(6) "abafoo"
var_dump(getItem($data, ['a', 'ab', 'abb']));
# NULL
var_dump(getItem($data, ['a', 'ab', 'abc']));
# bool(false)
try {
    getItem($data, ['a', 'ab', 'abe']);
} catch(Exception $e) {
    echo $e->getMessage();
}
# Undefined path: ["a","ab","abe"]

Note that this function can be improved, for example you can test if the parameters are arrays.