Youtube RegExp Compatible with preg_match_all

[GHRake]

Hello people of vbulletin, I've decided it's time to learn some php and write a vbulletin plugin.

So far so good:


But I'm having trouble with getting a rexexp to work with preg_match_all()
I'm getting the dreaded

"PHP Warning: preg_match_all(): Delimiter must not be alphanumeric or backslash"

When I use:

if (stripos($string, 'youtu') !== false)
{
$regex = 'https?:\/\/((.+\.youtube\.com\/watch\?v=)|(youtu\.be\/))([a-zA-Z0-9-_]+)';
preg_match_all($regex, $string, $matches);
if (!empty($matches))
{
     $og_array['og:video'] = $matches[2][0];
}
}

Any words of wisdom? TIA