WordPress 删除文章时自动删除对应文章的图片

WordPress默认是不删除图片的，因此会在媒体库造成大量图片冗余。

functions.php 中添加方法

#-----------------------------------------------------------------#
# 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：如果你的特色图片是用来作封面，并且经常复用的话，请删除 // 删除特色图片 下面的那段代码。