怎么设置wordpress标签自动内链？

function array2object($array) { // 数组转对象

if (is_array($array)) {

$obj = new StdClass();

foreach ($array as $key => $val){

$obj->$key = $val;

}

}

else {

$obj = $array;

}

return $obj;

}

function object2array($object) { // 对象转数组

if (is_object($object)) {

foreach ($object as $key => $value) {

$array[$key] = $value;

}

}

else {

$array = $object;

}

return $array;

}

add_action('save_post', 'auto_add_tags');

function auto_add_tags(){

$tags = get_tags( array('hide_empty' => false) );

$post_id = get_the_ID();

$post_content = get_post($post_id)->post_content;

if ($tags) {

$i = 0;

$arrs = object2array($tags);shuffle($arrs);$tags = array2object($arrs);// 打乱顺序

foreach ( $tags as $tag ) {

// 如果文章内容出现了已使用过的标签，自动添加这些标签

if ( strpos($post_content, $tag->name) !== false){

if ($i == 3) { // 控制输出数量

break;

}

wp_set_post_tags( $post_id, $tag->name, true );

$i++;

}

}

}

}

/* 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);

$url = "<span class='wp_keywordlink_affiliate'>< a href= "$link\" title=\"".str_replace('%s',addcslashes($cleankeyword, '$'),__('点击查看更多关于【%s】的文章'))."\"";

$url .= ' target="_blank"';

$url .= ">".addcslashes($cleankeyword, '$')."</ a></span>";

$limit = rand($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_repla