[RESOLVED] preg_match expression

areid

I need an expression that matches a-z and the underscore only. Everything else is rejected.

Example: I have a string that looks like this "gallery/[gallery_name]". I want to match "gallery_name". I've tried preg_match('/gallery\/[^a-z_]/i', $p), but it doesn't seem to work.

I want all of these to return true, anything other than a-z and the underscore to return falase.
gallery/numberone
gallery/number_one
gallery/number_one_a
gallery/number_one_a_b

I hope I made sense to someone!

As always, thanks for you help!

bradgrafelman

Well, your preg_match had a couple of errors. Here's what it should look like:

preg_match('@^gallery/[a-z_]+$@i', $p);

Modifications:

Used '@' as a delimiter instead of a forward slash (which you want to use literally in the pattern).
The '^......$' surrounding the pattern are start and end characters... basically means the string must be exactly what your pattern says - nothing more, nothing less.
Added the '+' modifier after the character class so that it matches "one or more" of those characters.

areid

Excellent! Thank you! Worked like it was supposed to. I'm not very good at regex :rolleyes:

bradgrafelman

areid wrote:
I'm not very good at regex :rolleyes:

To tell the truth, I'm no guru at it either. If you ever care to learn more (definitely a good syntax to learn, IMHO!), you should visit Regular-Expressions.info - top notch site about the complicated syntax (even has articles/examples of common tasks, e.g. validating e-mail addresses).