PHP Regex replace link if it does not have data attribute

Question

I need to loop through a bunch of HTML code and remove the <a> </a> tags from all links which DONT include the data attribute data-link="keepLink"

Here is an example of body value I need to modify:

<p><a data-link=\"keepLink\" href=\"[1|9999|16|191967|256]\">Daily Racing Link</a></p>\r\n<br>\n <strong>OFFER – Get&nbsp;up to a £400 deposit bonus when you sign up with&nbsp;<a href="https://gateway.tracker.com/track-989">Fanduel</a>.</strong>

After the modification I need it to look like (so the offer link is removed):

<p><a data-link=\"keepLink\" href=\"[1|9999|16|191967|256]\">Daily Racing Link</a></p>\r\n<br>\n <strong>OFFER – Get&nbsp;up to a £400 deposit bonus when you sign up with&nbsp; Fanduel.</strong>

So far I have managed to get the first half of the link removing if it doesn't include a data-link="keepLink" attribute. But the closing </a> is still present.

Here is the regex I have used:

$result["body_value"] = preg_replace('/<a (?![^>]*data-link="keepLink").*?>/i', '', $result["body_value"]);

So the new body value looks like:

<p><a data-link=\"keepLink\" href=\"[1|9999|16|191967|256]\">Daily Racing Link</a></p>\r\n<br>\n <strong>OFFER – Get&nbsp;up to a £400 deposit bonus when you sign up with&nbsp; Fanduel</a>.</strong>

This seems like a task you shouldn't use regex for and rely on a proper DOM parser. — Sebastian Proske, Dec 16 '16 at 10:23
Use DOMDocument to edit your html and DOMXPath to find the targets. — Casimir et Hippolyte, Dec 16 '16 at 10:23
@CasimiretHippolyte This http://us3.php.net/manual/en/class.domdocument.php? — smj2393, Dec 16 '16 at 10:25
@CasimiretHippolyte thanks I will take a look. Is there a reason I should use DOMDocument instead of the Regex? Sorry if that's a stupid question, but I am new to this. — smj2393, Dec 16 '16 at 10:38
The html language is very permissive and full of traps, a direct string approach can fail at any moment (for a quote, a whitespace, nested tags in a comment, in a Javascript string...). But the html language is also a structured language, and with a parser you build your code on this already existing structure. — Casimir et Hippolyte, Dec 16 '16 at 10:49
a.k.a http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags/1732454#1732454 — CD001, Dec 16 '16 at 10:50

Octavian · Accepted Answer · 2016-12-16T11:37:36.210

The DOMDocument extension is available by default in PHP. It is presumably faster and is designed exactly for what you are trying to achieve. You can use it to load your document and search for any links without a data-link attribute like this:

$dom = new DOMDocument;
$dom->loadHTMLFile('http://www.example.com'); // load the file

$xpath = new DOMXPath($dom);
$nodes = $xpath->query('//a[not(@data-link=\'keepLink\')]'); // search for links that do not have the 'data-link' attribute set to 'keepLink'

foreach($nodes as $element){
    $textInside = $element->nodeValue; // get the text inside the link
    $parentNode = $element->parentNode; // save parent node
    $parentNode->replaceChild(new DOMText($textInside), $element); // remove the element
}

$myNewHTML = $dom->saveHTML(); // see http://php.net/manual/ro/domdocument.savehtml.php for limitations such as auto-adding of doc-type

echo $myNewHTML;

Proof of concept: https://3v4l.org/ejatQ.

Please bear in mind that this will take only the text values inside the elements without a data-link='keepLink' attribute value.

Won't that remove the content of the `` as well as the tag? Whereas the desired result is `Fanduel` --> `Fanduel`. You need to replace the element with its text content rather than simply remove it. — CD001, Dec 16 '16 at 10:45

Fallenhero · Answer 2 · 2016-12-16T10:39:43.457

0

If you are set on regex and don't want to use a parser.

Try this

<a (?!data-link=)[^>]*>((?!<\/a>).*?)<\/a>

And replace it by $1. To keep your link-text.

See https://regex101.com/r/wKQk4p/2

Please say if you need any further explaination.

edited Dec 16 '16 at 10:39

answered Dec 16 '16 at 10:25

Fallenhero

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PHP Regex replace link if it does not have data attribute

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