## 要求 1. form表單的enctype取值必須是multipart/form-data(默認值是application/x-www-form-urlencoded). enctype:是表單請求正文的類型. 2. emthod必須是post. 3. 提供一個文件選擇域. ## 原理分析  ## 傳統文件上傳方式 導入依賴: ~~~ <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.5</version> </dependency> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.1</version> </dependency> ~~~ ~~~ <form action="/spring/upload" method="post" enctype="multipart/form-data"> <input type="file" name="upload"> <input type="submit"> </form> ~~~ ~~~ @RequestMapping(path = "/upload") public String testResponse(HttpServletRequest request, HttpServletResponse response) throws Exception { //使用fileupload組件完成上傳 String realPath = request.getSession().getServletContext().getRealPath("/uploads/"); //判斷該路徑是否存在 File file = new File(realPath); if (!file.exists()) { //創建文件夾 file.mkdirs(); } //獲取request對象,獲取文件項 DiskFileItemFactory diskFileItemFactory = new DiskFileItemFactory(); ServletFileUpload upload = new ServletFileUpload(diskFileItemFactory); //解析request List<FileItem> fileItems = upload.parseRequest(request); //遍歷 for (FileItem fileItem : fileItems) { //判斷當前item對憲法是否 是上傳文件項 if (fileItem.isFormField()) { //普通表單項 } else { //上傳文件項 //獲取文件的名稱 String filename = fileItem.getName(); //把文件名設為唯一 String s = UUID.randomUUID().toString().replace("-", ""); filename = s + "_" + filename; //完成文件上傳 fileItem.write(new File(realPath, filename)); //刪除臨時文件 fileItem.delete(); System.out.println("成功"); } } return "success"; } ~~~