我对magicgetter/isset有奇怪的问题。我有定义魔术getter/isset的myObject:private$_data=array();publicfunction__get($name){if(array_key_exists($name,$this->_data))return$this->_data[$name];thrownewException($name.':propertydoesn\'texist.');}publicfunction__isset($name){returnisset($this->_data[$name]);}如果我调用:isset(