To add to xafford's comment. When iterating a named node map collection using ->item() or using foreach, removing a attribute with DOMNode->removeAttribute() or DOMNode->removeAttributeNode() alters the collection as if it were a stack. To illustrate, the code below tries to remove all attributes from each element but only removes the first. One work around is to copy the named node map into an array before removing attributes. Using PHP 5.2.9 on Windows XP.
<?php
error_reporting(E_ALL);
$html = '<h1 id="h1test" class="h1test">Heading</h1>';
$html .= '<p align="left" class="ptest">Hello World</p>';
$doc = new DOMDocument();
$doc->loadHTML($html);
// remove attributes from the h1 element
$h1 = $doc->getElementsByTagName('h1')->item(0);
$length = $h1->attributes->length;
for ($i = 0; $i < $length; ++$i) {
$name = $h1->attributes->item($i)->name;
$h1->removeAttribute($name);
echo "h1: removed attribute `$name`<br>";
}
// remove attributes from the p element
$p = $doc->getElementsByTagName('p')->item(0);
foreach ($p->attributes as $name => $attrNode) {
$p->removeAttribute($name);
echo "p: removed attribute `$name`<br>";
}
?>
OUTPUT:
-------
h1: removed attribute `id`
Notice: Trying to get property of non-object in nodemap.php on line 13
h1: removed attribute ``
p: removed attribute `align`