Extract a parameter from URL using a regex in PHP

Question

I have a number of links that look like:

<a href="http://url.com/?foo=bar&p=20" title="foo">Foo</a>
<a href="http://url2.com/?foo=bar&p=30" title="foo">Foo</a>

I'm trying to extract the parameter p from each href found. So in this case I have an end result array as array (20, 30).

What would be a good regex for this? Thanks.

Like that? So invalid HTML? There isn't a good regex for it, use an HTML parser (one with good error recovery), extract the values of the href attributes, then run them through a URL parser. — Quentin
– Quentin, Commented Sep 29, 2010 at 17:30
You can't parse with regular expressions reliably. See below. — Andy Lester
– Andy Lester, Commented Sep 29, 2010 at 17:43
@FrustratedWithFormsDesigner: Yeah that's actually pretty close! Thanks — Vin
– Vin, Commented Sep 29, 2010 at 17:44
Suggested third party alternatives to SimpleHtmlDom that actually use DOM instead of String Parsing: phpQuery, Zend_Dom, QueryPath and FluentDom. — Gordon
– Gordon, Commented Sep 29, 2010 at 17:48

Gumbo · Accepted Answer · 2010-09-29 17:37:25Z

8

Don’t try to parse HTML with regular expressions; use an HTML parser like PHP’s DOM library or the PHP Simple HTML DOM Parser instead. Then parse the URL with parse_url and the query string with parse_str.

Here’s an example:

$html = str_get_html('…');
$p = array();
foreach ($html->find('a[href]') as $a) {
    parse_str(parse_url($a->getAttribute('href'), PHP_URL_QUERY), $args);
    if (isset($args['p'])) $p[] = $args['p'];
}

edited Sep 29, 2010 at 17:37

answered Sep 29, 2010 at 17:31

Gumbo

657k112 gold badges792 silver badges852 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Extract a parameter from URL using a regex in PHP

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related