PHP DOMDocument：按类删除元素

I' trying to delete every node with a given class.

To find the elements I use:

$xpath = new DOMXPath($dom);
    foreach( $xpath->query('//div[contains(attribute::class, "foo")]') as $e ) {
        // Delete this node
    }

But how can I delete the elements in this foreach-loop?

Edit: By the way: How can I check first if there is a element with the class "foo" in the DOM (before starting the loop)?

Update:

This is my HTML:

<div class="main">
    <div class="delete_this" contenteditable="true">Target</div>
    <div class="class1"></div>
    <div class="content"><p>Anything</p></div>
</div>

This doesn't work for the example above:

$xpath = new DOMXPath($dom);
foreach( $xpath->query('//div[contains(attribute::class, "delete_this")]') as $e ) {
    $e->parentNode->removeChild($e);
}

You need to use the removeChild() method of the parent element:

$xpath = new DOMXPath($dom);
foreach($xpath->query('//div[contains(attribute::class, "foo")]') as $e ) {
    // Delete this node
    $e->parentNode->removeChild($e);
}

Btw, about your second question, if there are no elements found, the loop won't iterate at all.

Here comes a working example:

$html = <<<EOF
<div class="main">
    <div class="delete_this" contenteditable="true">Target</div>
    <div class="class1"></div>
    <div class="content"><p>Anything</p></div>
</div>
EOF;

$doc = new DOMDocument();
$doc->loadHTML($html);

$selector = new DOMXPath($doc);
foreach($selector->query('//div[contains(attribute::class, "delete_this")]') as $e ) {
    $e->parentNode->removeChild($e);
}

echo $doc->saveHTML($doc->documentElement);

For the second part of the question, the result of the query has a length property which you can use to see if anything was matched:

$xpath = new DOMXPath($doc);
$nodes = $xpath->query('//div[contains(attribute::class, "foo")]');

printf('Removing %d nodes', $nodes->length);

This removes all divs with that class. To actually remove all the elements by class use *:

$selector = new \DOMXPath( $doc );
foreach ( $selector->query( '//*[contains(attribute::class, "' . $class . '")]' ) as $e ) {
  $e->parentNode->removeChild( $e );
}