Stripping microdata from an XHTML with PHP - using RegEx?_问答_开发者

Stripping microdata from an XHTML with PHP - using RegEx?

开发者 https://www.devze.com 2023-03-13 20:24 出处：网络

First: I\'ve read the general; don\'t use RegEx on XHTML arguments like this one: RegEx match open tags except XHTML self-contained tags and I do understand how RegEx will fail on nested XHTML or XML

First: I've read the general; don't use RegEx on XHTML arguments like this one: RegEx match open tags except XHTML self-contained tags and I do understand how RegEx will fail on nested XHTML or XML nodes.

I don't see why manipulating attributes of an XML alone should break using RegEx. So there seems to be exceptions to the general rule. Attributes are always contained in a single node starting with a &l开发者_运维问答t; and ending with a > any other < or > in between would break the XML so such can't occur.

Now I'd like to clean an XHTML string of any microdata it might contain. That is any attributes itemscope, itemtype, itemprop, itemid and itemref. Something like this:

...
<body itemscope="itemscope" itemtype="http://schema.org/WebPage">
<div itemprop="maincontent">content</div>
...

What's the best way to do this in PHP?

I'd actually suggest:

Loading the string with something like SimpleXML.
Removing the attributes you are interested in flushing.
Saving it back to a string.

There are a bunch of namespace issues that I'm not sure how you'd have to handle, but that will probably be cleaner/happier than trying to build one or more regex expressions and make sure you don't miss anything.

EDIT: turns out SimpleXML won't work (limited modification capabilities) but DOM will. Something like this:

$data=<<<END1
<body itemscope="itemscope" itemtype="http://schema.org/WebPage">
<div itemprop="maincontent">content</div>
</body>
END1;

$xml=new DOMDocument();
$xml->loadXML($data);

// find every relevant node
$xpath = new DOMXPath($xml);
$attr = $xpath->query("//@itemscope|//@itemprop|//@itemtype");
foreach ($attr as $entry) {
  $entry->parentNode->removeAttribute($entry->nodeName);
}
echo $xml->saveXML();

You'd have to modify it to include all the attributes you want to remove, and like I said I have no clue how it would deal with namespaces, but its a start.