I am currently using the Form Validation class (on Codeigniter) and setting rules.
It works like this with two parameters (codeigniter.com/user_guide/libraries/form_validation.html):
$this->form_validation->set_rules('username', 'Username', 'callback_test[abc]');
But what about a third parameter? And a fourth...? Is it possible?
It is not official but works
Split the parameter by ','