public function isError($key = null)
    {
        $value = $this->getError($key);
        return is_array($value) ? !empty($value) : isset($value);
    }
public function isError($key = null)
    {
        $value = $this->getError($key);
        return is_array($value) ? !empty($value) : isset($value);
    }
public function isError ( $ key = null ) { $ value = $ this -> getError ( $ key ) ; return is_array ( $ value ) ? ! empty ( $ value ) : isset ( $ value ) ; }
Whether a error exists
@param null|string $key
@return boolean
Whether a error exists