CodeIgniter form validation functions

codeigniter/libraries/Form_validation.php

    public function required($str)
    public function regex_match($str, $regex)
    public function matches($str, $field)
    public function is_unique($str, $field)
    public function min_length($str, $val)
    public function max_length($str, $val)
    public function exact_length($str, $val)
    public function valid_email($str)
    public function valid_emails($str)
    public function valid_ip($ip, $which = '')
    public function alpha($str)
    public function alpha_numeric($str)
    public function alpha_dash($str)
    public function numeric($str)
    public function is_numeric($str)
    public function integer($str)
    public function decimal($str)
    public function greater_than($str, $min)
    public function less_than($str, $max)
    public function is_natural($str)
    public function is_natural_no_zero($str)
    public function valid_base64($str)
    public function prep_for_form($data = '')
    public function prep_url($str = '')
    public function strip_image_tags($str)
    public function xss_clean($str)
    public function encode_php_tags($str)