$path=$_SERVER["DOCUMENT_ROOT"].'/books.xml';
    $books=new DOMDocument();
    $books->load($path);

$bookElements=$books->getElementsByTagName('book');

    foreach($bookElements as $book){
        foreach ($book->attributes as $attr) {
            echo strtoupper($attr->nodeName).' —— '.$attr->nodeValue.'br/>';
        }
        echo "AUTHOR: ";
        foreach ($book->getElementsByTagName('author') as $author) {
            echo $author->nodeValue.' ';
        }
        echo 'br/>br/>';
    }

echo $book->attributes->item(1)->nodeValue;

$xpath = new domxpath($books);
$bookElements=$xpath->query("/books/book");

foreach($bookElements as $book){
        foreach ($book->attributes as $attr) {
            #$book->setAttribute($attr->nodeName,strtoupper($attr->nodeValue));
            $attr->nodeValue=strtoupper($attr->nodeValue);
        }
        echo "AUTHOR: ";
        foreach ($book->getElementsByTagName('author') as $author) {
            $author->nodeValue=strtoupper($author->nodeValue);
        }

    }
    $books->save($path);

$book->setAttribute($attr->nodeName,strtoupper($attr->nodeValue));
$attr->nodeValue=strtoupper($attr->nodeValue);

$newBook=$books->createElement('book'); #創(chuàng)建新元素
    $newBook->setAttribute('name','PHP Objects, Patterns, and Practice');#創(chuàng)建新屬性，方法一

    $publisher=$books->createAttribute('publisher');#創(chuàng)建新屬性，方法二
    $publisher->nodeValue='Apress L.P';
    $newBook->appendChild($publisher); #把屬性添加到元素上

    $author=$books->createElement('author');#創(chuàng)建子元素
    $author->nodeValue='Matt Zandstra';
    $newBook->appendChild($author);#把子元素添加到父元素上

    $books->documentElement->appendChild($newBook);#添加整個節(jié)點
    $books->save($path);

$first=$bookElements->item(0);
    $first->removeAttribute('publisher');

    $second=$bookElements->item(1);
    $second->parentNode->removeChild($second);

    $books->save($path);