SpringMVC 使用 MultipartFile 实现文件上传

该代码实现了文件上传和文本字段同时传递到后台进行处理的功能。

直接贴代码，中间涉及到的实体类就不贴了，和功能没啥关系的。

Controller

     /**
      * 添加活动
      *
      * @param req
      * @param file1
      * @param file2
      * @return
      */
     @RequestMapping(value = "/addActivity", method = RequestMethod.POST)
     public JSONObject addActivity(HttpServletRequest req, @RequestParam(value = "file1") MultipartFile file1,
             @RequestParam(value = "file2") MultipartFile file2) {
         logger.info("enter into method addActivity");
         StatusCode statusCode = activityService.addActivity(req, file1, file2);
         return new ResultBuilder<>(statusCode).toJSONObject();
     }

Service

     /**
      * 添加活动
      * @param req
      * @param file1
      * @param file2
      * @return
      */
     public StatusCode addActivity(HttpServletRequest req, MultipartFile file1, MultipartFile file2) {
         try {
             //从request中获取上传的文件
             /*if(file1 == null){
                 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest)req;
                 file1 = multipartRequest.getFile("file1");
             }
             if(file2 == null){
                 MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest)req;
                 file2 = multipartRequest.getFile("file2");
             }*/

             if (file1 == null || file2 == null) {
                 logger.info("the file is null");
                 return StatusCode.FILE_IS_NULL;
             }

             String filepath1 = uploadFile(file1);
             String filepath2 = uploadFile(file2);
             if (filepath1 == null || filepath2 == null) {
                 logger.info("the file upload fail");
                 return StatusCode.FILE_UPLOAD_FAIL;
             }

             String activityname = req.getParameter("activityname");//活动名称
             String winrate = req.getParameter("winrate");//中奖率
             String expectedwinners = req.getParameter("expectedwinners");//预期中奖人数
             String daysnum = req.getParameter("daysnum");//每天首次访问小程序可获得的抽奖次数
             String firstnum = req.getParameter("firstnum");//首次关注公众号可获得的抽奖次数
             String sharelimitnum = req.getParameter("sharelimitnum");//每日分享最多可获得的抽奖次数
             String friendclicknum = req.getParameter("friendclicknum");//每日好友点击最多可获得的抽奖次数
             String ruledesc = req.getParameter("ruledesc");//规则描述
             String starttime = req.getParameter("starttime");//开始时间
             String endtime = req.getParameter("endtime");//结束时间
             String prizename = req.getParameter("prizename");//奖品名称
             String prizeprice = req.getParameter("prizeprice");//奖品价格
             String cardid = req.getParameter("cardid");//卡片ID

             if (StringUtils.isNullOrEmpty(activityname) || StringUtils.isNullOrEmpty(expectedwinners) || StringUtils.isNullOrEmpty(daysnum)
                     || StringUtils.isNullOrEmpty(firstnum) || StringUtils.isNullOrEmpty(sharelimitnum) || StringUtils.isNullOrEmpty(friendclicknum)
                     || StringUtils.isNullOrEmpty(ruledesc) || StringUtils.isNullOrEmpty(starttime) || StringUtils.isNullOrEmpty(endtime)
                     || StringUtils.isNullOrEmpty(prizename) || StringUtils.isNullOrEmpty(prizeprice) || StringUtils.isNullOrEmpty(cardid)
                     || StringUtils.isNullOrEmpty(winrate)) {
                 logger.info("the paramter is null or empty");
                 return StatusCode.REQUEST_PARAM_ERROR;
             }

             if (Long.parseLong(starttime) >= Long.parseLong(endtime)) {
                 logger.info("the starttime less than or equal to endtime");
                 return StatusCode.ACTIVITY_TIME_ERROR;
             }

             Activity activity = new Activity();
             activity.setActivityname(activityname);
             activity.setCoverimage(filepath1);
             activity.setThumbnail(filepath2);
             activity.setWinrate(Double.valueOf(winrate));
             activity.setExpectedwinners(Integer.valueOf(expectedwinners));
             activity.setDaysnum(Integer.valueOf(daysnum));
             activity.setFirstnum(Integer.valueOf(firstnum));
             activity.setSharelimitnum(Integer.valueOf(sharelimitnum));
             activity.setFriendclicknum(Integer.valueOf(friendclicknum));
             activity.setRuledesc(ruledesc);
             activity.setStarttime(new Date(Long.parseLong(starttime)));
             activity.setEndtime(new Date(Long.parseLong(endtime)));
             activity.setPrizename(prizename);
             activity.setPrizeprice(Double.valueOf(prizeprice));
             activity.setCardid(Integer.valueOf(cardid));

             int result = activityMapper.addActivity(activity);
             if (result != 1) {
                 logger.info("add activity fail");
                 return StatusCode.ADD_ACTIVITY_FAIL;
             }
         } catch (Exception e) {
             logger.error("add activity error", e);
             return StatusCode.FAIL;
         }
         return StatusCode.SUCCESS;
     }

     /**
      * 文件上传
      * @param file
      * @param savepath
      * @return
      */
     public String uploadFile(MultipartFile file){
         String savepath = Constants.UPLOAD_FILE_IMAGE_SAVE_PATH;
         File filedir = new File(savepath);
         //如果文件夹不存在则创建
         if (!filedir.exists()) {
             logger.info("create directory:{}", savepath);
             try{
                 filedir.mkdirs();
             }catch(Exception e){
                 logger.error("create directory fail", e);
                 return null;
             }
         }

         SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
         String nowdate = sdf.format(new Date(System.currentTimeMillis()));

         String originalfilename = file.getOriginalFilename();
         if (originalfilename == null || !originalfilename.contains(".")) {
             logger.info("file name is error:{}", originalfilename);
             return null;
         }
         String suffix = originalfilename.substring(originalfilename.indexOf("."));
         String filepath = savepath + nowdate + suffix;

         File targetFile = new File(filepath);
         try {
             file.transferTo(targetFile);
         } catch (Exception e) {
             logger.error("file upload fail", e);
             return null;
         }
         return filepath;
     }

使用FORM的话需要指定enctype="multipart/form-data"

附上我测试用的form表单

   <form action="http://localhost:8080/activity/addActivity" method="post" enctype="multipart/form-data">
     activityname<input type="text" name="activityname" value="第一个测试活动"/><br>
     expectedwinners<input type="text" name="expectedwinners" value="100"/><br>
     daysnum<input type="text" name="daysnum" value="3"/><br>
     firstnum<input type="text" name="firstnum" value="5"/><br>
     sharelimitnum<input type="text" name="sharelimitnum" value="6"/><br>
     friendclicknum<input type="text" name="friendclicknum" value="7"/><br>
     ruledesc<input type="text" name="ruledesc" value="这里简单描述下规则，自己写啊。"/><br>
     starttime<input type="text" name="starttime" value="1519292136927"/><br>
     endtime<input type="text" name="endtime" value="1519293136927"/><br>
     prizename<input type="text" name="prizename" value="笔记本电脑"/><br>
     prizeprice<input type="text" name="prizeprice" value="5999.56"/><br>
     cardid<input type="text" name="cardid" value="1"/><br>
     <input type="file" name="file1"/><br>
     <input type="file" name="file2"/><br>
     <input type="submit" value="提交"/>
   </form>