preg_match(); - Unknown modifier '+'

Question

Alright, so I'm currently working on parsing an RSS feed. I've gotten the data I need no problem, and all I have left is parsing the game title.

Here is the code I currently have (ignore the sloppiness, it is just a proof of concept):

<?php
$url = 'http://raptr.com/conexion/rss';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); 
$result = curl_exec($ch); 
curl_close($ch);

$xml = new SimpleXMLElement($result);

$lastgame = $xml->channel->item[0]->description;
preg_match('[a-zA-Z]+</a>.$', $lastgame, $match);

echo $match;
?>

Everything was working great, but then I started getting this error:

Warning: preg_match() [function.preg-match]: 
Unknown modifier '+' in raptr.php on line 14

The only thing I have left is to strip out the closing anchor tag and the period, but I can't seem to figure out why it isn't liking the '+'. Any ideas?

Edit: This should not be marked as a duplicate as it was asked two years before the other question.

Solution 1

You need to use delimiters with regexes in PHP. You can use the often used /, but PHP lets you use any matching characters, so @ and # are popular.

Further Reading.

If you are interpolating variables inside your regex, be sure to pass the delimiter you chose as the second argument to preg_quote().

Solution 2

Try this code:

preg_match('/[a-zA-Z]+<\/a>.$/', $lastgame, $match);
print_r($match);

Using / as a delimiter means you also need to escape it here, like so: <\/a>.

UPDATE

preg_match('/<a.*<a.*>(.*)</', $lastgame, $match);
echo'['.$match[1].']';

Might not be the best way...

Solution 3

This happened to me because I put a variable in the regex and sometimes its string value included a slash. Solution: preg_quote.

Solution 4

May be this will be usefull for u: ReGExp on-line editor

View more solutions

Comments

[David Bradbury]

print_r($match); returns "Array ( )"I'm pretty sure my expression is correct.

[Khez]

I don't know what you tried to say with your comment...

[Khez]

@Conexion, checked your other comments, what is it you are trying to pull from that rss feed into your match ? The games ?

[David Bradbury]

Yup, just trying to pull the most recent game :)

[David Bradbury]

It works, but the problem is, the feed doesn't always being with "played some". Sorry I'm being difficult!

[Khez]

Updated my code yet again, considered this time you always have <a>USER</a> <a>Game</a> in that order.

[Shane N]

Thank you for letting me know about preg_quote - very useful function!

[stamster]

Well, that was a surprise. string preg_quote ( string $str [, string $delimiter = NULL ] ) -> function signature forces nothing as default, thus kicked me in the balls when least expected. Default should be /.