wp_set_object_terms not working inside loop

Question

I have the following code

$genres= array('action', 'comedy', 'horror');
foreach($genres as $genre){
      $ret = wp_set_object_terms( $postId, $genre, 'genres');
}

But this code associates only horror as the genre. When I checked the DB too, I don't have a record for action and comedy. How do I associate all the three with my genre?

Thanks in advance.

Answer 1

You can pass an array of terms to wp_set_object_terms, there is no need for the for each:

$genres= array('action', 'comedy', 'horror');
$ret = wp_set_object_terms( $postId, $genres, 'genres');

Answer 2

@Bainternet's answer got me on the right track, for storing a comma separated string of tags as individual tags in the database and associate each individual tag with the proper post.

I needed this, because I have a form field which allows users to enter a list of comma separated tags.

Anyway, here's the complete code I use:

// Sanitize user/form input
$custom_tags = trim(htmlspecialchars($_POST['custom_tags']));
// Explode returns the comma separated terms as an array
$custom_tags_separated = explode(',', $custom_tags);
// Pass the array of terms to wp_set_object_terms
wp_set_object_terms($post_id, $custom_tags_separated, 'custom_tag');