Form validation rules for regex_match

Question

I\'m trying to figure out what I\'m doing wrong with this validation rule because its saying this error.

Validation rule:

$this->form_validation-&         


        

Answer 1

php's preg_match wants your regular expression surrounded by a non alpha-numeric character (usually everyone uses /), change your setRules() to this:

$this->form_validation->set_rules('username', 'Username', 'trim|required|xss_clean|regex_match[/a-z0-9/]');