How to use create_term, edit_term, delete_term actions?

Question

I've created a Custom Taxonomy and I want to hook a function when User adds new Term to my Custom Taxonomy. Can someone please show me how to use following actions in Wordpress?

1. create_term
2. edit_term
3. delete term

All these actions are defined in wp-includes/taxonomy.php as follows:

do_action("create_term", $term_id, $tt_id, $taxonomy);
do_action("edit_term", $term_id, $tt_id, $taxonomy);
do_action('delete_term', $term, $tt_id, $taxonomy);

Whenever I try to hook my function with add_action, the Custom Taxonomy page works indifferently. Page does not refresh when I add/edit new Taxonomy Term and attempting to delete any existing term gives me error: "An undefined error occurred." Actually all changes are getting registered to Database... page doesn't refresh on add/edit, but the Term is added/changed successfully. Even delete action actually deletes the term; I can see the changes when I refresh the page.

I think there is something which the function may need to return... something is holding the Wordpress back and I just don't know what's going wrong.

Waiting for your valuable reply...

Regards,

Ruturaaj.

Answer 1

There's not much to it, you don't need to return anything. Note that you also can't output anything to the browser, that will cause it to fail.

function my_create( $term_id, $tt_id, $taxonomy ){
    // do some stuff
}
add_action( 'create_term', 'my_create', 10, 3 );

You mention using this with a custom taxonomy, note that there are also actions that let you hook specific taxonomies:

do_action("create_$taxonomy", $term_id, $tt_id);

Answer 2

To update this, since wp 3.5, the "delete_term" action provides 4 parameters now (http://core.trac.wordpress.org/ticket/20645).

do_action( 'delete_term', $term, $tt_id, $taxonomy, $deleted_term );

where $term is the term id and $deleted_term is the term object.