springboot 上传下载
前端代码, 使用thymeleaf
<form th:action="@{/employee/upload2}" method="post" enctype="multipart/form-data"> 姓名: <input type="text" name="lastName"> <br> 年龄: <input type="text" name="age"> <br> 邮箱: <input type="email" name="email"> <br> 文件: <input type="file" name="file"> <br> desc: <input type="text" name="desc"> <input type="submit" value="提交"> </form> <hr> <form th:action="@{/employee/multiup2}" method="post" enctype="multipart/form-data"> 文件<input type="file" name="file"> <br> 文件<input type="file" name="file"> <br> 文件<input type="file" name="file"> <br> <input type="submit" value="提交"> </form> <hr> <!--常量参数要加引号--> <a th:href="@{/employee/down(filename='图片.PNG')}">下载图片</a> <br> <a th:href="@{/employee/down(filename='2.PNG')}">下载2</a> </body>
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下载路径
@ResponseBody @RequestMapping("/get/{id}") public Employee getRest(@PathVariable("id") Integer id, HttpServletRequest request) { //D:\workspace_for_idea\springboot\springboot-test\src\main\webapp System.out.println(request.getServletContext().getRealPath("/")); //D:\workspace_for_idea\springboot\springboot-test\. System.out.println(new File(".").getAbsolutePath()); //D:\ System.out.println(new File("/").getAbsolutePath()); //D:\workspace_for_idea\springboot\springboot-upload-download\ String path = System.getProperty("user.dir"); return employeeService.getById(id); }
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单个文件上传
/* 单独文件上传 */ @ResponseBody @PostMapping("/upload1") public String upload1(String desc, Employee employee, @RequestParam("file") MultipartFile multipartFile) throws IOException { //上传的文件不能为空 if (multipartFile.isEmpty()) { return "上传失败, 请选择文件"; } //springboot对封装的对象自动做了处理,能直接拿到值,但是springMvc不能 System.out.println(employee); System.out.println(desc); //D:\workspace_for_idea\springboot\springboot-upload-download\ //获取当前项目所在位置 String filename = multipartFile.getOriginalFilename(); System.out.println("文件大小===>" + multipartFile.getSize()); System.out.println("上传文件类型===>" + multipartFile.getContentType()); //获取根路径 String path = System.getProperty("user.dir"); File file = new File(path + "/files/" + filename); //判断父目录是否存在 if (!file.getParentFile().exists()) { //新建文件 file.getParentFile().mkdir(); } String absolutePath = file.getAbsolutePath(); System.out.println("文件路径===>" + absolutePath); multipartFile.transferTo(file); return "上传成功upload1"; } @ResponseBody @PostMapping("/upload2") public String upload2(@RequestParam("file") MultipartFile multipartFile) { if (multipartFile.isEmpty()) { return "上传失败, 请选择文件"; } String filename = multipartFile.getOriginalFilename(); System.out.println("filename===>" + filename); System.out.println("文件大小===>" + multipartFile.getSize()); System.out.println("contentType===>" + multipartFile.getContentType()); String path = System.getProperty("user.dir"); //两种方式获取文件后缀名,正则中. 用\\.表示 System.out.println(filename.split("\\.")[1]); String suffix = filename.substring(filename.indexOf(".") + 1); System.out.println("文件后缀名" + suffix); //忽略大小写判断文件格式 if (!(suffix.equalsIgnoreCase("png") || suffix.equalsIgnoreCase("jpg"))) { return "文件格式错误"; } File file = new File(path + "/files/" + filename); if (!file.getParentFile().exists()) { file.getParentFile().mkdir(); } String absolutePath = file.getAbsolutePath(); System.out.println("文件路径===>" + absolutePath); try { multipartFile.transferTo(file); return "上传成功"; } catch (IOException e) { e.printStackTrace(); } return "失败upload2"; }
/* 多文件上传 也可以采用 @RequestParam("file") Multipart[] 来作为参数 */ @ResponseBody @PostMapping("/multiup1") public String multiUpLoad(HttpServletRequest request) { //getFile中的name对应前端的name List<MultipartFile> files = ((MultipartHttpServletRequest) request).getFiles("file"); for (int i = 0; i < files.size(); i++) { MultipartFile file = files.get(i); //必须上传文件 if (file.isEmpty()) { log.info("上传第" + (i + 1) + "个文件失败"); return "上传第" + (i + 1) + "个文件失败"; } String filename = file.getOriginalFilename(); String path = request.getServletContext().getRealPath("/files"); File filePath = new File(path + "/" + filename); if (!filePath.getParentFile().exists()) { filePath.getParentFile().mkdir(); } try { log.info("上传第" + (i + 1) + "个文件成功"); file.transferTo(filePath); } catch (IOException e) { log.info("上传第" + (i + 1) + "个文件失败"); e.printStackTrace(); return "上传第" + (i + 1) + "个文件失败"; } } return "上传成功multiup1"; } /* stream多文件上传 */ @ResponseBody @PostMapping("/multiup2") public String multiUpload(@RequestParam("file") MultipartFile[] files) { //可以通过stream流操作,流操作一定要有终止操作才会正真的执行 Long collect = Arrays.stream(files).map(this::upload2).collect(Collectors.counting()); log.info(collect + "个文件上传成功"); return "上传成功multiup2"; }
下载文件
/* 下载文件 */ @GetMapping("/down") public void download(HttpServletRequest request, HttpServletResponse response, @RequestParam String filename) throws IOException { String header = request.getHeader("User-Agent"); // String path="files"+File.separator+filename; String path = Paths.get("files", filename).toString(); System.out.println("filename==========>" + filename); //设置消息头 response.setContentType("application/force-download");//强制下载不打开 //消息头,固定格式, filename这里是文件的名字 response.addHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(filename, "utf-8")); try (FileInputStream fis = new FileInputStream(path); BufferedInputStream bis = new BufferedInputStream(fis); ServletOutputStream responseOutputStream = response.getOutputStream()) { byte[] buffer = new byte[1024]; int len = -1; while ((len = bis.read(buffer)) != -1) { responseOutputStream.write(buffer, 0, len); } } }
