Selecting style attribute with REGEX in PHP

Question

I'm looking to get only the style attribute and it's contents using regex in php.

For example

Input <img src="test.png" style="float:left;"/>

Desired Output style="float:left;"

What i've tried:

This seems to return the entire image, and i'm not sure why. I suck at regex.

$img = '<img src="test.png" style="float:left;"/>';
preg_match('/(<[^>]+) style=".*?"/i', $img, $match);

Returns:

    [0] => Array
    (
        [0] => <img src="test.png" style="float:left;"
        [1] => <img src="test.png"
    )

Anyone with any pointers?

Cheers.

`style` attribute? Please see [RegEx match open tags except XHTML self-contained tags](http://stackoverflow.com/q/1732348/112968) on why RegEx is not always the right tool for the job. — knittl, Aug 28 '13 at 14:25
Yeah I understand that, but in this situation i _have_ to use regex unfortunately. — Greg, Aug 28 '13 at 14:26
@Greg: Why can't you _not_ use RegEx? I'm really interested in the reason. — knittl, Aug 28 '13 at 14:33
@Knittl I'm working with some messy code I've inherited and don't have the time to adapt the rest of the code to use XML parsing — Greg, Aug 28 '13 at 14:37
You don't have to adapt the rest (although it would be good). If the rest works as is, leave it alone. — knittl, Aug 28 '13 at 14:38

score 5 · Accepted Answer · answered Aug 28 '13 at 14:28

You have it almost correct, you just need to capture the part you want, by surrounding it in parenthesis. You're currently capturing the wrong part:

$img = '<img src="test.png" style="float:left;"/>';
preg_match('/<[^>]+ (style=".*?")/i', $img, $match);
$result = $match[1];

Demo

Note: This will work for simple inputs like the example <img> tag, but for anything more complex Regex is not powerful enough to parse HTML, since HTML is not a regular language. If you find that it's not powerful enough you can use DOMDocument, which is meant for this sort of thing.

Brilliant, thanks! It's literally as simple as my example, so Regex works fine for now. If I had the choice I'd definitely use DOMDocument parsing. Thanks again! — Greg, Aug 28 '13 at 14:38

Selecting style attribute with REGEX in PHP

1 Answers1