WordPress 自动为文章添加标签内链、文章自动添加标签

/**
 * WordPress 自动为文章标签添加该标签的链接
 * https://www.wpdaxue.com/auto-add-tag-link.html
 */
function wpkj_auto_add_tag_link($content){
    $limit = 1; // 设置同一个标签添加几次链接
    $posttags = get_the_tags();
    if ($posttags) {
        foreach($posttags as $tag) {
            $link = get_tag_link($tag->term_id);
            $keyword = $tag->name;
            $cleankeyword = stripslashes($keyword);
            $url = '<a target="_blank" href="'.$link.'" title="'.str_replace('%s', addcslashes($cleankeyword, '$'), __('View all posts in %s')).'">'.addcslashes($cleankeyword, '$').'</a>';
            $regEx = '\'(?!((<.*?)|(<a.*?)))('. $cleankeyword . ')(?!(([^<>]*?)>)|([^>]*?</a>))\'s';
            $content = preg_replace($regEx,$url,$content,$limit);
        }
    }
    return $content;
}
add_filter( 'the_content', 'wpkj_auto_add_tag_link', 1 );

* WordPress文章关键词自动添加内链链接代码 */
//连接数量
$match_num_from = 1; //一篇文章中同一个关键字少于多少不锚文本（这个直接填1就好了）
$match_num_to = 1; //一篇文章中同一个关键字最多出现多少次锚文本（建议不超过1次）
//连接到WordPress的模块
add_filter('the_content','tag_link',1);
//按长度排序
function tag_sort($a, $b){
if ( $a->name == $b->name ) return 0;
return ( strlen($a->name) > strlen($b->name) ) ? -1 : 1;
}
//改变标签关键字
function tag_link($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;
//连接代码
$cleankeyword = stripslashes($keyword);
$url = "<a href=\"$link\" title=\"".str_replace('%s',addcslashes($cleankeyword, '$'),__('查看所有文章关于 %s'))."\"";
$url .= 'target="_blank"';
$url .= ">".addcslashes($cleankeyword, '$')."</a>";
$limit = rand($match_num_from,$match_num_to);
//不连接的代码
$content = preg_replace( '|(<a[^>]+>)(.*)('.$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; 
}

以上代码的功能就是在我们发布/保存/更新文章时，自动检测文章中的内容，是否出现标签内容。如果出现过就会自动为文章内的标签添加内链。