How to remove parent section in an attachment URL in wordpress?

Question

In wordpress, an unattached attachment URL is

http://domain.com/?attachment=$id

Once after it's attached to a parent, it goes with parent's URL structure, for example:

http://domain.com/parent-title/attachment-title

I need my attachments URL contains only root domain as the unattached ones. How to make it?

Answer 1

You can add a filter to the function that gets attachment links to force that format:

function wpa60888_attachment_link( $link, $id ){
    return home_url() . '/?attachment_id=' . $id;
}
add_filter( 'attachment_link', 'wpa60888_attachment_link', 10, 2 );

Calls to get_attachment_link will have this filter applied to the output.