java - 如果附件不可用，ajaxform 不会提交值

Question

我是一名 Java 初学者，打算创建一个 Web 应用程序。我正在使用 ajaxform 向 Controller 提交一份表单。元素很少，其中之一是 type=file。

我的 Controller 方法如下

    @RequestMapping(value = { "/addReplies" }, method = {
        org.springframework.web.bind.annotation.RequestMethod.POST,
        org.springframework.web.bind.annotation.RequestMethod.GET } )
@ResponseBody
public Map<String,Object> addReplies(
        @Valid @ModelAttribute("Replies") Replies replies,
        BindingResult result, HttpServletRequest request,
        HttpServletResponse response,Locale locale,Principal principal,
        @RequestParam(value = "fileData2",required=false) CommonsMultipartFile fileData2[]) throws ServletException,
        IOException {
             //perform some opraton
        }

如果数据中有可用附件，则一切正常工作，否则不会进入此方法。

如果我从方法中删除 @RequestParam(value = "fileData2",required=false) CommonsMultipartFile fileData2[] 此参数，则可以正常工作，但通过这种方式我无法获取附件。

请尝试理解我的问题并尽快给我所有可能的解决方案。

如果我不使用ajax并使用regul提交表单，此方法效果很好

Answer 1

我也这样做但我的编码也可以工作

执行此解决方案

@RequestMapping(value="/saveUserTask", method=RequestMethod.POST)
@ResponseBody
public Map<String,String> saveUserTask(
        @RequestParam( value = "title" , required = false) String title,
        @RequestParam( value = "projectid" , required = false) int projectid,
        @RequestParam( value = "mileid" , required = false,defaultValue ="-1") int mileid,
        @RequestParam( value = "responsible" , required = false) int responsible[],
        @RequestParam( value = "startDate" , required = false) Date startDate,
        @RequestParam( value = "endDate" , required = false) Date endDate,
        @RequestParam( value = "description" , required = false) String description,
        @RequestParam( value = "priority" , required = false, defaultValue="1") int priority,
        @RequestParam( value = "workHours" , required = false) int workHours,
        @RequestParam(value = "attachment" , required = false) MultipartFile myFile,
        HttpServletRequest request,Principal principal,RedirectAttributes redirectAttributes,Locale locale) throws ParseException, IOException{
    String fileAttachPath;
    if(myFile!=null)
        fileAttachPath=request.getSession().getServletContext().getRealPath("/WEB-INF/attechments/"+ new Date().getTime() + "_" + myFile.getOriginalFilename());
    else
        fileAttachPath="";
}