Basic regex PHP issue

I am trying to grab the articleId which is formatted as follows:

开发者_如何学JAVA    articleId=1234567

Here is the code I am using

    $regex = 'articleId\=[0-9]{7}';
    preg_match_all($regex,$data,$match);
    for ($i=0; $i< count($match[0]); $i++) {
        echo "".$match[1][$i]."]";
    }

I am receiving the following error: preg_match_all() [function.preg-match-all]: Delimiter must not be alphanumeric or backslash

FWIW I am using 5.2.17

place delimiters in your regexp, like this:

$regex = '/articleId=[0-9]{7}/';

also, there is no need to escape equal sign

You forgot your '/'

preg_match_all('/' . $regex . '/',$data,$match);

or alternatively

$regex = '/articleId\=[0-9]{7}/';