WordPress删除文章同时自动删除缩略图及图片附件。

/* 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');