If the element is in fact a group, it will be considered as a whole, an array of group elements' values will be passed to validation function. To validate grouped elements as separate entities, use addGroupRule().
Parameter
mixed
$element
Form element name(s). Currently the only builtin rule that expects and correctly handles an array here is compare:
$form->addElement('password', 'cmpPasswd', 'Password:');
$form->addElement('password', 'cmpRepeat', 'Repeat password:');
$form->addRule(array('cmpPasswd', 'cmpRepeat'), 'The passwords do not match', 'compare', null, 'client');
All other builtin rules will only handle a single element name.
string
$message
Message to display for invalid data
string
$type
Rule type, use getRegisteredRules() to get types. You can also pass a classname for a descendant of HTML_QuickForm_Rule or an instance of such class.
string
$format
(optional) Required for extra rule data
string
$validation
(optional) Where to perform validation: "server", "client"
boolean
$reset
For client-side validation: reset the form element to it's original value if there is an error?
boolean
$force
Force the rule to be applied, even if the target form element does not exist