php: htmlescape but $tags

htmlescape.php

<?php

/**
 * htmlescape but $tags 
 * 
 * @see http://jp.php.net/manual/ja/function.htmlspecialchars.php
 * @param string $str 
 * @param string $tags delimiter "|". i.e. 'a|div|span'
 * @param string $quote_style 
 * @param string $l_deli '##{##' 
 * @param string $r_deli '##}##'
 * @access public
 * @return string
 */
function htmlescape( $str, $tags = '', $quote_style = ENT_NOQUOTES, $l_deli = '##{##', $r_deli = '##}##' ) {
    if ( !$tags ) {
        return htmlspecialchars( $str, $quote_style );
    }
    
    $reg = '#<(/?[^<>]*\b(?:' . $tags . ')\b[^<>]*)>#ie';
    
    $buf = preg_replace( $reg, "_htmlescape('$l_deli\\1$r_deli')", $str );
    $buf = htmlspecialchars( $buf, $quote_style );
    
    $searches = array(
        $l_deli,
        $r_deli,
    );
    $replacements = array(
        '<',
        '>',
    );
    
    return str_replace( $searches, $replacements, $buf );
}

function _htmlescape( $match ) {
    $order = array(
        "\r\n",
        "\n",
        "\r",
    );
    $match = str_replace( $order, '', $match );
    $match = str_replace( '\"', '"', $match );
    
    return $match;
}