WordPress SEO优化 如何自动为文章添加标签链接增加站点内链

/* 自动为文章内的标签添加内链 */
$match_num_from = 1;        //一篇文章中同一个标签少于几次不自动链接
$match_num_to = 1;      //一篇文章中同一个标签最多自动链接几次
function tag_sort($a, $b){
    if ( $a->name == $b->name ) return 0;
    return ( strlen($a->name) > strlen($b->name) ) ? -1 : 1;
}
function tag_link($content){
    global $match_num_from,$match_num_to;
        $posttags = get_the_tags();
        if ($posttags) {
            usort($posttags, \"tag_sort\");
            foreach($posttags as $tag) {
                $link = get_tag_link($tag->term_id);
                $keyword = $tag->name;
                $cleankeyword = stripslashes($keyword);
                $url = \"<a href=\\\"$link\\\" title=\\\"\".str_replace(\'%s\',addcslashes($cleankeyword, \'$\'),__(\'【查看含有[%s]标签的文章】\')).\"\\\"\";
                $url .= \' target=\"_blank\"\';
                $url .= \">\".addcslashes($cleankeyword, \'$\').\"</a>\";
                $limit = rand($match_num_from,$match_num_to);
                $content = preg_replace( \'|(<a[^>]+>)(.*)(\'.$ex_word.\')(.*)(</a[^>]*>)|U\'.$case, \'$1$2%&&&&&%$4$5\', $content);
                $content = preg_replace( \'|(<img)(.*?)(\'.$ex_word.\')(.*?)(>)|U\'.$case, \'$1$2%&&&&&%$4$5\', $content);
                $cleankeyword = preg_quote($cleankeyword,\'\\\'\');
                $regEx = \'\\\'(?!((<.*?)|(<a.*?)))(\'. $cleankeyword . \')(?!(([^<>]*?)>)|([^>]*?</a>))\\\'s\' . $case;
                $content = preg_replace($regEx,$url,$content,$limit);
                $content = str_replace( \'%&&&&&%\', stripslashes($ex_word), $content);
            }
        }
    return $content;
}
add_filter(\'the_content\',\'tag_link\',1);