public function isValidPhone($phone, $old_phone = null)
{
$res = preg_match($this->_phone_reg, $phone, $matches) !== 0;
if (!$res) {
$this->_error = '无效的手机号';
}
if ($res && $this->_user_model->where('`phone`="' . mysql_escape_string($phone) . '"')->find() and $phone != $old_phone) {
$this->_error = '该手机号已被注册';
$res = false;
}
return (bool) $res;
}