class DateValidator extends CustomValidator
{
 
    private $form_element;
 
    public function __construct($form_element)
    {
        $this->form_element = $form_element;
    }
 
    function DoValidate(&$formars, &$error_hash)
    {
        $date = $formars[$this->form_element];
 
        //check that input conforms to basic structure
        if (!preg_match('/^[0-9]{1,2}\/[0-9]{1,2}\/[0-9]{4}$/', $date))
        {
            $error_hash[$this->form_element] = "Date Invalid - Format is day/month/year for example 1/1/2010 or 26/09/2011";
            return false;
        }
 
        // break the date into a list and use checkdate to confirm the date is a valid real date
        list( $d, $m, $y ) = preg_split('/[-\.\/ ]/', $date);
        if (checkdate($m, $d, $y))
        {
            return true;
        }
        else
        {
            $error_hash[$this->form_element] = "That date does not exist, Format is day/month/year for example 1/1/2010 or 26/09/2011";
            return false;
        }
    }
 
}