How to delete all post and attachments of a user when I delete it?

Question

When I delete a user, WordPress can just delete the post or page of this user, not his custom post and his attachments.

An idea for a special hook?

add_action( 'delete_user', 'my_delete_user');

function my_delete_user($user_id) {
    $user = get_user_by('id', $user_id);
    $the_query = new WP_Query( $args );
        if ( have_posts() ) { 
            while ( have_posts() ) { 
                the_post(); 
                    wp_delete_post( $post->ID, false ); 

                    // HOW TO DELETE ATTACHMENTS ?
            }
        }
}

Answer 1

The hook you choose is appropriate, and here is how to use it to delete all posts of all types (posts, pages, links, attachments, etc) of the deleted user:

add_action('delete_user', 'my_delete_user');
function my_delete_user($user_id) {
    $args = array (
        'numberposts' => -1,
        'post_type' => 'any',
        'author' => $user_id
    );
    // get all posts by this user: posts, pages, attachments, etc..
    $user_posts = get_posts($args);

    if (empty($user_posts)) return;

    // delete all the user posts
    foreach ($user_posts as $user_post) {
        wp_delete_post($user_post->ID, true);
    }
}

If you only want to delete user attachments, change the post_type arguments from any to attachment and use wp_delete_attachment($attachment_id) instead of wp_delete_post().