在多维数组中用值替换值

Question

I need to replace all values in a multidimensional array by their respective key, but only if the value is not an array.

From:

array(
    'key1' => array(
        'key2' => array(
            'key3' => 'val'
        )
    )
);

To:

array(
    'key1' => array(
        'key2' => array(
            'key3'
        )
    )
);

Does anyone know a way to do this nicely?

Answer 1

This seems to do more or less what you want (fiddle):

<?php
function convert($arr) {
    $ret = array();
    foreach ($arr as $key => $value) {
        if (is_array($value)) {
            $ret[$key] = convert($value);
        } else {
            $ret[] = $key;
        }
    }
    return $ret;
}
$test = array(
    'key1' => array(
        'key2' => array(
            'key3' => 'val'
        )
    )
);
var_dump(convert($test));

Output:

array(1) {
  ["key1"]=>
  array(1) {
    ["key2"]=>
    array(1) {
      [0]=>
      string(4) "key3"
    }
  }
}