WordPress网站删除文章的同时自动删除缩略图及图片附件

WordPress建站后期，当我们想要删除文章的时候，发现文章里上传到媒体库的图片等附件并不会自动删除，这样占用了大量的网站空间，下面我们介绍一下在删除文章时自动删除缩略图以及图片附件的方法，只需几句简单的代码便可实现，不用手动去媒体库寻找并删除，准确率和效率都非常高。

切换到主题目录，打开functions.php文件，加入以下代码：

/* 删除文章时删除图片附件
/* ------------------------ */
function delete_post_and_attachments($post_ID) {
        global $wpdb;
        //删除特色图片
        $thumbnails = $wpdb->get_results( "SELECT * FROM $wpdb->postmeta WHERE meta_key = '_thumbnail_id' AND post_id = $post_ID" );
        foreach ( $thumbnails as $thumbnail ) {
        wp_delete_attachment( $thumbnail->meta_value, true );
        }
        //删除图片附件
        $attachments = $wpdb->get_results( "SELECT * FROM $wpdb->posts WHERE post_parent = $post_ID AND post_type = 'attachment'" );
        foreach ( $attachments as $attachment ) {
        wp_delete_attachment( $attachment->ID, true );
        }
        $wpdb->query( "DELETE FROM $wpdb->postmeta WHERE meta_key = '_thumbnail_id' AND post_id = $post_ID" );
}
add_action('before_delete_post', 'delete_post_and_attachments');

/* 删除文章时删除图片附件

/* ------------------------ */

function delete_post_and_attachments($post_ID) {

global $wpdb;

//删除特色图片

$thumbnails = $wpdb->get_results( "SELECT * FROM $wpdb->postmeta WHERE meta_key = '_thumbnail_id' AND post_id = $post_ID" );

foreach ( $thumbnails as $thumbnail ) {

wp_delete_attachment( $thumbnail->meta_value, true );

}

//删除图片附件

$attachments = $wpdb->get_results( "SELECT * FROM $wpdb->posts WHERE post_parent = $post_ID AND post_type = 'attachment'" );

foreach ( $attachments as $attachment ) {

wp_delete_attachment( $attachment->ID, true );

}

$wpdb->query( "DELETE FROM $wpdb->postmeta WHERE meta_key = '_thumbnail_id' AND post_id = $post_ID" );

}

add_action('before_delete_post', 'delete_post_and_attachments');

注意：此处使用的是 before_delete_post 这个 action ，而不是 delete_post 。如果使用的是 delete_post 这个 action 将导致删除文章后因媒体附件与文章关联已取消而无法正确删除。