strip_word_html.php

<?php
    function strip_word_html(
        $text,
        $allowed_tags = '<a><ul><li><b><i><sup><sub><em><strong><u><br><br/><br /><p><h2><h3><h4><h5><h6>'
    ) {
        mb_regex_encoding('UTF-8');
        //replace MS special characters first
        $search = array('/&lsquo;/u', '/&rsquo;/u', '/&ldquo;/u', '/&rdquo;/u', '/&mdash;/u');
        $replace = array('\'', '\'', '"', '"', '-');
        $text = preg_replace($search, $replace, $text);
        //make sure _all_ html entities are converted to the plain ascii equivalents - it appears
        //in some MS headers, some html entities are encoded and some aren't
        //$text = html_entity_decode($text, ENT_QUOTES, 'UTF-8');
        //try to strip out any C style comments first, since these, embedded in html comments, seem to
        //prevent strip_tags from removing html comments (MS Word introduced combination)
        if (mb_stripos($text, '/*') !== false) {
            $text = mb_eregi_replace('#/\*.*?\*/#s', '', $text, 'm');
        }
        //introduce a space into any arithmetic expressions that could be caught by strip_tags so that they won't be
        //'<1' becomes '< 1'(note: somewhat application specific)
        $text = preg_replace(array('/<([0-9]+)/'), array('< $1'), $text);
        $text = strip_tags($text, $allowed_tags);
        //eliminate extraneous whitespace from start and end of line, or anywhere there are two or more spaces, convert it to one
        $text = preg_replace(array('/^\s\s+/', '/\s\s+$/', '/\s\s+/u'), array('', '', ' '), $text);
        //strip out inline css and simplify style tags
        $search = array(
            '#<(strong|b)[^>]*>(.*?)</(strong|b)>#isu',
            '#<(em|i)[^>]*>(.*?)</(em|i)>#isu',
            '#<u[^>]*>(.*?)</u>#isu'
        );
        $replace = array('<b>$2</b>', '<i>$2</i>', '<u>$1</u>');
        $text = preg_replace($search, $replace, $text);
        //on some of the ?newer MS Word exports, where you get conditionals of the form 'if gte mso 9', etc., it appears
        //that whatever is in one of the html comments prevents strip_tags from eradicating the html comment that contains
        //some MS Style Definitions - this last bit gets rid of any leftover comments */
        $num_matches = preg_match_all("/\<!--/u", $text, $matches);
        if ($num_matches) {
            $text = preg_replace('/\<!--(.)*--\>/isu', '', $text);
        }
        $text = preg_replace('/(<[^>]+) style=".*?"/i', '$1', $text);

        return $text;
    }