PHP：转换多维数组

Question

Given the following array:

Array
(
  [entity] => Array
    (
      [title] => Array
        (
          [empty] => error message
        )
      [link] => Array
        (
          [empty] => error message
        )
      [authors] => Array
        (
          [0] => Array
            (
              [full_name] => Array
                (
                  [max_lengh] => another error message 2
                )
            )
        )
    )
)

How to convert it into a form like:

$array = [
'entity[title]' => 'error message',
'entity[link]' => 'error message',
'entity[authors][0][full_name]' => 'another error message 2',
];

I think this is done via recursion or use the references but the two things I'm not good) Thanking you in advance!

Answer 1

Maybe not properly explained to the task. Thanks to all.

function format(array $array, $withLastKey = false) {
        $iterator = new RecursiveIteratorIterator(
            new RecursiveArrayIterator($array));
        $returnArray = [];
        foreach ($iterator as $key => $value) {
            $keys = [];
            for ($i = $iterator->getDepth(); $i >= 0; $i--) {
                $childKey = $iterator->getSubIterator($i)->key();
                // if first element then without bracket
                $keys[] = ($i == 0) ? $childKey : '[' . $childKey . ']';
            }
            $keys = array_reverse($keys);
            ($withLastKey) ?: array_pop($keys);
            $returnArray[implode('', $keys)] = $value;
        }
        return $returnArray;
    }