springmvc_ajax异步上传文件(基于ajaxfileupload.js)

引入js

  <script th:src="@{/js/ajaxfileupload.js}"></script>

html

<tr>
        <td>附件:</td>
        <td>
             <input type="hidden" id="insertcyefuji"  name="fuji" />
             <input type="file"  id="uploadcyefuji"  name="file" />
        </td>
</tr>

js代码-----选择完文件后自动上传

$('input[id="uploadcyefuji"]').change(function(e){
              var formData = new FormData();
                formData.append('file', $('#uploadcyefuji')[0].files[0]);
                $.ajax({
                    url: '/fileUpload',
                    type: 'POST',
                    cache: false,
                    data: formData,
                    processData: false,
                    contentType: false
                }).done(function(res) {
                    alert("上传成功")
                }).fail(function(res) {
                    alert("上传失败");
                });

 })

controller后台代码

 /**
      * 实现文件上传
      * @throws IOException
      * @throws IllegalStateException
      * */
     @RequestMapping(value="fileUpload",method = RequestMethod.POST)
     @ResponseBody
     public String fileUpload(HttpServletRequest req,MultipartFile file) throws IllegalStateException, IOException{
         if(file.getOriginalFilename()==null||file.getOriginalFilename().equals("")){
             System.err.println("为空++++");
             return "";
         }else{
             String picName = UUID.randomUUID().toString();
             // 获取文件名
             String oriName = file.getOriginalFilename();
                 System.err.println(oriName+"图片名字");
             // 获取图片后缀
             String extName = oriName.substring(oriName.lastIndexOf("."));
                 System.err.println("后缀名字"+extName);
             if(extName.equals(".jpg") || extName.equals(".JPG")  ||extName.equals(".png") ||  extName.equals(".PNG")){
                 String path = req.getSession().getServletContext().getRealPath("/");
                 System.out.println("path="+path);

                 file.transferTo(new File(path+"upload/"+picName + extName));
                 //user.setUsername(picName + extName);
                 //m.addAttribute("fileName"+count, picName + extName);
                 //count--;
                 //list.add(user);

                 // 设置图片名到商品中
                 System.err.println("上传图片完成");
                 return "上传成功";
             }else {
                 System.err.println("格式不对");
                 return "格式不对"; 

             }
         }
 }