Matching Unicode letter characters in PCRE/PHP

Question

I'm trying to write a reasonably permissive validator for names in PHP, and my first attempt consists of the following pattern:

// unicode letters, apostrophe, hyphen, space
$namePattern = "/^([\\p{L}'\\- ])+$/";

This is eventually passed to a call to preg_match(). As far as I can tell, this works with your vanilla ASCII alphabet, but seems to trip up on spicier characters like Ă or 张.

Is there something wrong with the pattern itself? Perhaps I'm expecting \p{L} to do more work than I think it does?

Or does it have something to do with the way input is being passed in? I'm not sure if it's relevant, but I did make sure to specify a UTF8 encoding on the form page.

Answer 1

I think the problem is much simpler than that: You forgot to specify the u modifier. The Unicode character properties are only available in UTF-8 mode.

Your regex should be:

// unicode letters, apostrophe, hyphen, space
$namePattern = '/^[-\' \p{L}]+$/u';