PHP从xml获取所有属性

<bookstore>
  <book category="cooking">
    <title lang="en">The Joy of Cooking</title>
    <author>John Doe</author>
    <year>2005</year>
    <price>25.00</price>
  </book>
  <book category="fiction">
    <title lang="en">Harry Potter</title>
    <author>J.K. Rowling</author>
    <year>2003</year>
    <price>29.99</price>
  </book>
</bookstore>

$xml = simplexml_load_file('example.xml');

foreach ($xml->children() as $book) {
  foreach ($book->attributes() as $name => $value) {
    echo $name . ': ' . $value . '<br>';
  }
}

category: cooking
lang: en
category: fiction
lang: en