Excuse the html email. It means I can highlight things and hence communicate more clearly.

First, I think you have an extra '+' character, which results in a double plus '++' being passed into preg_match()

$regex = "(\s*([a-z][a-z0-9\-]*)\s*:\s*([a-z][a-z0-9\-]*)\s*;) +";
if (preg_match('/'. $regex .' +/i', $text, $matches)) {...

which calls preg_match('/(\s*([a-z][a-z0-9\-]*)\s*:\s*([a-z][a-z0-9\-]*)\s*;) ++/i', 'style="font-style: italic; font-weight: bold;"', $matches))

Nevertheless, that's not the cause, because removing one or both plusses doesn't solve the problem.

The thing that strikes me as odd with this regex is the wrapping of the outer parenthesis, in a multiplier. I would instead look for a way of repeating the smaller regex on the string until the string is finished. This code;

$text = 'style="font-style: italic; font-weight: bold;"';
$regex = "\s*([a-z][a-z0-9\-]*)\s*:\s*([a-z][a-z0-9\-]*)\s*;";
if (preg_match_all('/'. $regex .'/i', $text, $matches, PREG_SET_ORDER)) {
print_r($matches);
}

returns this;

Array
(
    [0] => Array
        (
            [0] => font-style: italic;
            [1] => font-style
            [2] => italic
        )

    [1] => Array
        (
            [0] =>  font-weight: bold;

            [1] => font-weight
            [2] => bold
        )

)

Which I think is more similar to what you are seeking?

Also, I expect there is probably a php library that does this with simpler function calls than writing you're own ajax. Possibly as part of or related to the DOM class and related classes http://nz.php.net/manual/en/ref.dom.php

Cheers,
Bevan/

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