映射XML文件，将属性保存为键

I have a XML that looks like this:

<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
<lang>
  <data type="array">
     <languageKey index="default" type="array">
       <label index="name">Full Name</label>
       <label index="sex">Gender</label>
     </languageKey>
     <languageKey index="es" type="array">
       <label index="name">Nombre Completo</label>
       <label index="sex">Género</label>
     </languageKey>
  </data>
</lang>

And I need to convert it to an object or array keeping the index attribute as key of the value.

Ex:

$lang = array (
  'default' => array (
     'name' => 'Full Name',
     'sex' => 'Gender'
  ),
  'es' => array (
     'name' => 'Nombre Completo',
     'sex' => 'Género'
  )
);

I tried with simplexml_load_file() but it eliminates the index and create numeric keys.

I'd use DomDocument. If the data structure will be exactly like given then you could

$xml = <<<XML
<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
<lang>
  <data type="array">
     <languageKey index="default" type="array">
       <label index="name">Full Name</label>
       <label index="sex">Gender</label>
     </languageKey>
     <languageKey index="es" type="array">
       <label index="name">Nombre Completo</label>
       <label index="sex">Género</label>
     </languageKey>
  </data>
</lang>
XML;

$dom = new DOMDocument();
@$dom->loadXML($xml);
$elements = $dom->getElementsByTagName('languageKey');
$return = array();
foreach($elements as $element){
  $tokens = explode("
", trim($element->nodeValue));
  $key = $element->getAttribute('index');
  $return[$key] = array(
    'name' => trim($tokens[0]),
    'sex' => trim($tokens[1])
  );
}

echo '<pre>' . print_r($return, true) . '</pre>';

OUTPUT

Array
(
    [default] => Array
        (
            [name] => Full Name
            [sex] => Gender
        )

    [es] => Array
        (
            [name] => Nombre Completo
            [sex] => Género
        )

)

EDIT

Changing the foreach you can find elements within previous results:

foreach($elements as $element){
  $key = $element->getAttribute('index');
  // here we'll get label elements
  $labels = $element->getElementsByTagname('label');
  foreach($labels as $label){
    // use index attribute as key
    $key2 = $label->getAttribute('index');
    $return[$key][$key2] = trim($label->nodeValue);
  }
}

This is more generic and easily adaptable for anything

Trying to figure out a solution I developed this function:

// Carga un archivo XML de idioma y lo convierte en un array para su consulta.
function loadXMLfile($file){

    // Carga el contenido del archivo.
    $file_content = file_get_contents($file);

    preg_match_all('/<languageKey(.+?)>(.+?)<\/languageKey>/is', $file_content, $lang_blocks);

    // Obtiene las etiquetas de idioma.
    foreach ($lang_blocks[1] as $meta_data){
        preg_match_all('/index="(.+?)"/is', $meta_data, $lang);
        $langs[] = $lang[1][0];
    }

    // Obtiene los textos
    foreach ($lang_blocks[2] as $texts){
        preg_match_all('/<label index="(.+?)">(.+?)<\/label>/is', $texts, $label);
        $labels[] = array_combine($label[1],$label[2]);
    }        

    return array_combine($langs,$labels);
}