preg_match for HTML 5

Question

How would I formulte the pattern so I would extract the XXXX-XX-XX out of a time tag?

The line I'm searching for in a $string is this:

<time datetime="XXXX-XXX-XX" itemprop="birth">

And I want to extract the part:

XXXX-XX-XX

I have this but it's not working:

preg_match('\<time datetime="d{4}-d{2}-d{2}"',$string,$date);
echo $date[0] . "<br />";

I find regex expressions so damn confusing ... any good tutorial recommendation would also be great! Appreciate your time and help.

Cheers

I think you'd be better off using PHP's methods of parsing XML on the file in question. — esqew, Jan 24 '12 at 16:06
I would use an HTML/XML parser, find the element and just read the value of the `datetime` attribute. — Felix Kling, Jan 24 '12 at 16:06
possible duplicate of [Grabbing the href attribute of an A element](http://stackoverflow.com/questions/3820666/grabbing-the-href-attribute-of-an-a-element) — Felix Kling, Jan 24 '12 at 16:07
http://gskinner.com/RegExr/ is handy for quick testing of regexes. — Juuso Ohtonen, Jan 24 '12 at 16:08
PHP has a built-in XML parser, which is the best way to go. Your example (and those in the answers) will massively fail on ` — Herbert, Jan 24 '12 at 16:16

score 3 · Accepted Answer · answered Jan 24 '12 at 16:07

3

You need to use \d in place of just d.

Also you need to enclose the regex in pair of delimiter.

Like:

preg_match('/\<time datetime="\d{4}-\d{2}-\d{2}"/',$string,$date);

answered Jan 24 '12 at 16:07

codaddict

Thank you for taking the time! – Afonso Gomes Jan 24 '12 at 16:17
I'm getting an error of undefined offset 1 ... I think it's because sometimes I get the itemprop="birth" between – Afonso Gomes Jan 24 '12 at 16:26
Nevermind! Dumb question :) Got it working now! Thanks again. – Afonso Gomes Jan 24 '12 at 16:28

Tim Pietzcker · Answer 2 · 2012-01-24T16:13:42.870

2

You forgot the delimiters, some escapes and a capturing group:

preg_match('/<time datetime="(\d{4}-\d{2}-\d{2})"/',$string,$date);
echo $date[1] . "<br />";

edited Jan 24 '12 at 16:13

answered Jan 24 '12 at 16:07

Tim Pietzcker

Thank you! Seems I wasn't that far from it and yet so far I was! – Afonso Gomes Jan 24 '12 at 16:16

score 1 · Answer 3 · answered Jan 24 '12 at 16:07

1

Your pattern needs the /../

preg_match('/\<time datetime="d{4}-d{2}-d{2}"/',$string,$date);

Edit: See tim's answer, you need the capture group too.

answered Jan 24 '12 at 16:07

Michael Dillon

Thank you for taking the time! – Afonso Gomes Jan 24 '12 at 16:18
@MichaelDillon Some of your recent edits are bad. Please stop doing this: `I would recommend http://www.pdfsharp.net/` => `I would recommend [this]`. Replacing the link text with the word `this` is a *bad edit*. At the very least, make it `I would recommend [PDF Sharp](http://...)`. – user229044 Jan 24 '12 at 19:02
@MichaelDillon Your other edits are generally very welcome, fyi. – user229044 Jan 24 '12 at 19:19
@meagar I admittedly got a little lazy ;) – Michael Dillon Jan 24 '12 at 19:20

3 Answers3