Reputation: 928

Preg_match doesn't work while trying to get numbers in a string

Hum.. I mean I can't make it work... So here is what I did..

$url = 'http://test/test/9244349';
$test = preg_match('#\d*#', $url, $matches);

array (size=1) 0 => string '' (length=0)

I just want to catch "9244349" but I don't figure out why it's not working.

Upvotes: 1

Answers (4)

Reputation: 336158

Let's play regex engine:

\d* means any number of digits. Including zero.
We start at the beginning of the string. We see an h.
h doesn't match \d.
But - we're also allowed to match zero repetitions of \d. So the empty string before h matches.
We've reached the end of the regex, and we've found a match.
Achievement unlocked!
(of course, it's a match of zero characters, but that's OK. A Perl-compatible regex will always return the leftmost possible match, even if there may be further matches up ahead in the string that could be longer).

So, as mentioned in other posts, change the * to + to force at least one digit to match, then the rest will follow.

You could also use preg_match_all(), but then you'd get a lot of empty matches, one for each position between two non-digits...

Upvotes: 1

Reputation: 86386

echo basename($url);

Upvotes: 0

Reputation: 76395

Try replacing * with +, if you want to match digits, there's no point in a pattern that matches, zero digits, too, is there?

preg_match('/\d+/','http://test/test/9244349',$matches);
echo $matches[0];//output:9244349

Upvotes: 1

Reputation: 5546

Change * to + and it will work

Upvotes: 0