当挂钩可以修改使用时，您不需要编辑WordPress核心文件，也不需要这样做the_excerpt_rss 和the_content_feed 筛选以在提要中添加缩略图或自定义链接。

add_filter( \'the_excerpt_rss\', \'insert_thumbnail_into_feed\' );
add_filter( \'the_content_feed\', \'insert_thumbnail_into_feed\' );

function insert_thumbnail_into_feed() {
    global $post;
    if ( has_post_thumbnail( $post->ID ) ){
        // replace thumbnail with yours
        $content = \'<p>\' .get_the_post_thumbnail( $post->ID, \'thumbnail\' ) .\'</p>\';
    }

    // get post content and replace feed content with
    // you can also limit/filter the content to exclude shortcodes and html code etc.
    $content .= \'<p>\' .get_the_content() .\'</p>\';

    return $content;
}