layui 图片上传+表单提交+ Spring MVC的实例

<div class="layui-form-item">
 <label class="layui-form-label">修改头像</label>
 <div class="layui-input-inline uploadHeadImage">
  <div class="layui-upload-drag" id="headImg">
   <i class="layui-icon">?v</i>
   <p>点击上传图片，或将图片拖拽到此处</p>
  </div>
 </div>
 <div class="layui-input-inline">
  <div class="layui-upload-list">
   <img class="layui-upload-img headImage" src="http://t.cn/RCzsdCq" id="demo1">
   <p id="demoText"></p>
  </div>
 </div>
</div>

<script type="text/javascript">
 layui.use(["jquery", "upload", "form", "layer", "element"], function () {
  var $ = layui.$,
   element = layui.element,
   layer = layui.layer,
   upload = layui.upload,
   form = layui.form;
  //拖拽上传
  var uploadInst = upload.render({
   elem: '#headImg'
   , url: '/upload/headImg'
   , size: 500
   , before: function (obj) {
    //预读本地文件示例，不支持ie8
    obj.preview(function (index, file, result) {
     $('#demo1').attr('src', result); //图片链接（base64）
    });
   }
   , done: function (res) {
    //如果上传失败
    if (res.code > 0) {
     return layer.msg('上传失败');
    }
    //上传成功
    //打印后台传回的地址: 把地址放入一个隐藏的input中, 和表单一起提交到后台, 此处略..
    /* console.log(res.data.src);*/
    window.parent.uploadHeadImage(res.data.src);
    var demoText = $('#demoText');
    demoText.html('<span style="color: #8f8f8f;">上传成功!!!</span>');
   }
   , error: function () {
    //演示失败状态，并实现重传
    var demoText = $('#demoText');
    demoText.html('<span style="color: #FF5722;">上传失败</span> <a class="layui-btn layui-btn-mini demo-reload">重试</a>');
    demoText.find('.demo-reload').on('click', function () {
     uploadInst.upload();
    });
   }
  });
  element.init();
 });
</script>

/**
 * 个人信息上传
 * @return {Result}
 */
@RequestMapping(value = "/upload/headImg", method = {RequestMethod.POST})
@ResponseBody
public Object headImg(@RequestParam(value="file",required=false) MultipartFile file, HttpServletRequest request, HttpServletResponse response) throws Exception {
 if (SecurityUtils.getSubject().isAuthenticated() == false) {
  return "redirect:/backEnd/login";
 }
 String prefix="";
 String dateStr="";
 //保存上传
  OutputStream out = null;
 InputStream fileInput=null;
 try{
  if(file!=null){
   String originalName = file.getOriginalFilename();
   prefix=originalName.substring(originalName.lastIndexOf(".")+1);
    dateStr = format.format(new Date());
   String filepath = request.getServletContext().getRealPath("/static") + uploadDir + dateStr + "." + prefix;
   filepath = filepath.replace("\\", "/");
   File files=new File(filepath);
   //打印查看上传路径
   System.out.println(filepath);
   if(!files.getParentFile().exists()){
    files.getParentFile().mkdirs();
   }
   file.transferTo(files);
  }
 }catch (Exception e){
 }finally{
  try {
   if(out!=null){
    out.close();
   }
   if(fileInput!=null){
    fileInput.close();
   }
  } catch (IOException e) {
  }
 }
 Map<String,Object> map2=new HashMap<>();
 Map<String,Object> map=new HashMap<>();
 map.put("code",0);
 map.put("msg","");
 map.put("data",map2);
 map2.put("src","../../../static"+uploadDir + dateStr + "." + prefix);
 return map;
}