thinkphp中连接oracle时封装方法无法用的解决办法

public function index() {
        header("Content-Type:text/html; charset=utf-8");

        $M_User = new UserModel();

        $User_List = $M_User->select();

        $this->assign(‘Title‘, ‘用户管理‘);

        $this->assign(‘UserList‘, $User_List);

        $this->display();
}

    //添加用户提交处理
public function Create_Post() {
        $M_User = new UserModel();
        $data[‘username‘] = $this->_post(‘username‘);
        $data[‘password‘] = md5($this->_post(‘pwd‘));

        if ($M_User->create()) {
            $Query_Result = $M_User->add($data);
            if (false !== $Query_Result) {
                $this->success(‘用户添加成功‘);
            } else {
                $this->error(‘用户添加错误‘);
            }
        } else {
            header("Content-Type:text/html; charset=utf-8");
            exit($M_User->getError() . ‘ [ <a href="javascript:history.back()">返 回</a> ]‘);
        }
}

$M_User=new UserModel();

$M_User->create();

$Query_Result = $M_User->add($data);

?protected $fields = array(
            ‘id‘, ‘username‘, ‘password‘
        );