Re: preg_match question: locating unmatched HTML tags

Hi, Saturday, February 22, 2003, 12:35:15 PM, you wrote: AC> My apologies in advance if this too basic or there's a solution easily AC> found out there, but after lots of searching, I'm still lost. AC> I'm trying to build a regexp that would parse user-supplied text and AC> identify cases where HTML tags are left open or are not properly AC> matched-e.g., <b> tags without closing </b> tags. This is for a sort of AC> message board type of application, and I'd like to allow users to use AC> some HTML, but just would like to check to ensure that no stray tags are AC> input that would screw up the rest of the page's display. I'm new to AC> regular expressions, and the one below is as far as I've gotten. If AC> anyone has any suggestions, they'd be very much appreciated. AC> Thanks, AC> Andy AC> $suspect_tags = "b|i|u|strong|em|font|a|ol|ul|blockquote "; AC> $pattern = '/<(' . $suspect_tags . '[^>]*>)(.*)(?!<\/\1)/Ui'; AC> if (preg_match($pattern,$_POST['entry'],$matches)) { AC> //do something to report the unclosed tags AC> } else { AC> echo 'Input looks fine. No unmatched tags.'; AC> } The simplest is just to add </b></i></textarea></whatever else you allow> directly to the end of their message, may not be technically correct but it won't do any harm either :) -- regards, Tom