UploadFile::error PHP Method

    protected function error($errorNo)
    {
        switch ($errorNo) {
            case 1:
                $size = ini_get('upload_max_filesize');
                if (strpos($size, 'M') !== false || strpos($size, 'm') !== false) {
                    $size = intval($size) * 1024;
                    $size = byte_format($size);
                }
                //edit by  yangjs
                if (isset($this->maxSize) && !empty($this->maxSize)) {
                    $size = byte_format($this->maxSize);
                }
                $this->error = '上传文件大小不符，文件不能超过 ' . $size;
                break;
            case 2:
                $size = ini_get('upload_max_filesize');
                if (strpos($size, 'M') !== false || strpos($size, 'm') !== false) {
                    $size = intval($size) * 1024;
                    $size = byte_format($size);
                }
                //edit by  yangjs
                if (isset($this->maxSize) && !empty($this->maxSize)) {
                    $size = byte_format($this->maxSize);
                }
                $this->error = '上传文件大小不符，文件不能超过 ' . $size;
                break;
            case 3:
                $this->error = '文件只有部分被上传';
                break;
            case 4:
                $this->error = '没有文件被上传';
                break;
            case 6:
                $this->error = '找不到临时文件夹';
                break;
            case 7:
                $this->error = '文件写入失败';
                break;
            default:
                $this->error = '未知上传错误！';
        }
        return;
    }

 /**
  * 添加/修改文章
  */
 public function save()
 {
     if (!empty($_POST['id']) && !ctype_digit($_POST['id'])) {
         $this->failure(Core::getLang('invalid_request'));
     }
     // 如果有文件上传
     if ($_FILES['title_image']['error'] != UPLOAD_ERR_NO_FILE) {
         $options = array('type' => 'image', 'max_size' => 1024000, 'save_path' => IMG_PATH . 'article/', 'save_rule' => '##Ymd/');
         $upload = new UploadFile($options);
         // 上传错误提示错误信息
         if (!$upload->upload()) {
             $this->failure($upload->error());
         } else {
             // 上传成功 获取上传文件信息
             $_POST['title_image'] = $upload->fileList['title_image']['savename'];
         }
     } else {
         $_POST['title_image'] = '';
     }
     $_POST['editor_uid'] = $_SESSION['uid'];
     $_POST['editor'] = $_SESSION['username'];
     $_POST['post_time'] = strtotime($_POST['post_time']);
     // 		if (!isset($_POST['brief'])) {
     // 			$_POST['brief'] = '';
     // 		}
     // 		$_POST['content'] = '';
     $mo = new Model_Article();
     if ($mo->save($_POST)) {
         $this->success(Core::getLang('handle_success'), 'admin.php?a=article');
     } else {
         if ($mo->msg) {
             $msg = $mo->msg;
         } else {
             $msg = Core::getLang('save_article_data_fail');
         }
         $this->failure($msg);
     }
 }