public function __get($k)
{
if (isset($this->_fields->{$k})) {
return $this->_fields->{$k};
} else {
//判断是不是属于外键
foreach ($this->foreign_keys as $k2 => $v2) {
$tmp = explode(".", $v2);
if (!empty($tmp[0]) && !empty($tmp[1])) {
$tbl_name = trim($tmp[0]);
if ($k == $tbl_name) {
return $this->_fields->{$k} = new stdclass();
}
}
}
}
return null;
}