thinkphp3.2.3----图片上传并生成缩率图

public function uploadify(){
    if(!IS_POST){
        $this->error('非法！');
    }
    $upload = $this->_upload();
}

protected function _upload(){
    $obj = new \Think\Upload();
    $obj->exts = array('jpg', 'gif', 'png', 'jpeg');// 设置附件上传类型
    $obj->rootPath = './data/upload/';    //upload类、image类的./入口目录
    $obj->savePath = 'face/';
    $obj->saveRule = 'uniqid';
    $obj->uploadReplace = true;
    $obj->autoSub = true;
    $obj->subType = 'date';
    $obj->dateFormat = 'Y_m';
    $info = $obj->upload();
    $userinfo = $this->users_model->where(array('id' => $this->userid))->find();
    if(!$info) {// 上传错误提示错误信息
        $this->error($obj->getError());
    }else{// 上传成功
        $face = './data/upload/'.$info['face']['savepath'].$info['face']['savename'];
        // 生成缩略图128*128；
        $image = new \Think\Image(); 
        $image->open($face);
        // 按照原图的比例生成一个最大为150*150的缩略图并保存为thumb.jpg
        $image->thumb(128, 128)->save($face);
      M('users')->where(array('id' => $this->userid))->save(array('avatar' => $info['face']['savepath'].$info['face']['savename']));
      if($userinfo['avatar']){
           @unlink('./data/upload/'.$userinfo['avatar']);//删除旧图
      }
      redirect(U('user/profile/upload_face'));
    }
}