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"; 
               
            }
        }
}