Validating forms with regex in codeigniter

Question

How can I validate a form using regex in codeiginiter. I'd like to check the input against:

^([0-1][0-9]|[2][0-3]):([0-5][0-9])$

I'm assuming the best way is in some sort of callback. I tried a bunch of ideas on the web but I can't seem to get any working.

Answer 1

Old post but you can add the regex directly in the input validation rule

$this->form_validation->set_rules()

Add to function above: regex_match[your regex]