validateAttribute() public method Validates a single attribute

$skipOnEmpty public property Whether this validation rule should

$when public property A PHP callable whose return value determines

addError() public method Adds an error about the specified

$attributes public property Attributes to be validated by this

validateValue() protected method Validates a value.

$builtInValidators public static property List of built-in validators

clientValidateAttribute() public method Returns the JavaScript

$isEmpty public property A PHP callable that replaces the default

isActive() public method Returns a value indicating whether