使用SimpleXML使用命名空间解析XML

$xml = simplexml_load_file('example.xml');
// 或者
$xml = simplexml_load_string($xml_string);

$ns = 'http://www.example.com/ns';
$title = $xml->children($ns)->title;

foreach ($xml->children($ns)->book as $book) {
    echo $book->title . PHP_EOL;
}

$author = $book->author->attributes($ns)->name;

$new_book = $xml->addChild('book', null, $ns);
$new_book->addChild('title', 'New Book Title', $ns);
$new_book->addChild('author')->addAttribute('name', 'John Doe', $ns);