php - regex to match div tags

Question

I'm using regex to match specific div's in a page and replace them with a custom formatted one. I can't use domdocument as often the pages we process are mal-formed and after running it through domdocument, the pages are reformatted and don't display the same.

I'm currently using the following which works perfectly:

preg_match('#(\<div id=[\'|"]'.$key.'[\'|"](.*?)\>)(.*?)\<\/div\>#s', $contents, $response);

To match div tags such as:

<div id="test"></div>
<div id="test" style="width: 300px; height: 200px;"></div>
etc...

The problem I'm encountering is tags where the id is after the style or class, example:

<div class="test" id="test"></div>

If I run the following, the regex seems to become greedy and matches a ton of html before the div tag, so I'm not sure how to fix this:

preg_match('#(\<div(.*?)id=[\'|"]'.$key.'[\'|"](.*?)\>)(.*?)\<\/div\>#s', $contents, $response);

Does anyone have any ideas?

take a look at this, might be somewhat helpful to you: http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags — Mohammad AbuShady, Apr 14 '14 at 16:19
[Obligatory link](http://stackoverflow.com/q/4231382/471272). — tchrist, Jun 08 '14 at 20:00

score 4 · Accepted Answer · answered Apr 14 '14 at 16:16

4

You can use the Ungreedy modifer (U), and also - do not use .*, but [^>]* (which means anything that is not > as > is the end of the tag and you are searching withing the tag). You don't need to escape / when this is not your delimiter (you are using # as delimiter)

preg_match('#(<div[^>]*id=[\'|"]'.$key.'[\'|"][^>]*>)(.*)</div>#isU', $contents, $response);

answered Apr 14 '14 at 16:16

Maxim Krizhanovsky

24,757
5
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+1 `[^>]*` is super valuable when Regex parsing HTML. – iambriansreed Apr 14 '14 at 16:19
I <3 stack overflow, thanks a ton for the answer. I'll accept it when the time delay is over in 10 minutes. – Joe Apr 14 '14 at 16:20

score 0 · Answer 2 · answered Apr 14 '14 at 16:38

0

Don't use regex for HTML parsing, there are DOM parsers out there, like PHP DOM: http://www.php.net/manual/en/book.dom.php

answered Apr 14 '14 at 16:38

Rafał Walczak

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Right, but to use them, you need a valid dom, which can mean tidy first, then implementing the dom object, and that can be a lot of overhead. Sometimes, especially when you're looking for specific bits of information, it doesn't make sense to go through the whole ritual of Dom parsing, when you can write a simple regular expression in two lines of code. – Yitzhak Oct 17 '15 at 00:13
There's no need to be afraid of this stuff. It's only a chainsaw. – Yitzhak Oct 17 '15 at 00:17

php - regex to match div tags

2 Answers2