文件下载

1.文件下载后端代码

/**
     * 初始化下载页面
     *
     * @return
     */
    @RequestMapping(value = "/initDownloadPage", method = RequestMethod.GET)
    public String initDownloadPage(Model model) {
        File file = new File("D:/File");
　　　　　// 获取文件列表
        if (file.exists() && file.isDirectory()) {
            String[] files = file.list();
            if (files.length > 0) {
                model.addAttribute("fileList", files);
            } else {
                System.out.print("空！");
            }
        } else {
            System.out.print("路径不存在！");
        }
        return "download";
    }

    /**
     * 文件下载
     *
     * @param fileName
     * @param response
     * @throws Exception
     */
    @RequestMapping(value = "/downloadFile", method = RequestMethod.GET)
    public void downloadFile(@RequestParam("fileName") String fileName,
                             HttpServletResponse response) throws Exception {
        // 如果文件名不为空，则进行下载
        if (fileName != null) {
            //设置文件路径
            String realPath = "D:/File/";
            File file = new File(realPath, fileName);
            // 如果文件名存在，则进行下载
            if (file.exists()) {
                // 配置响应头
                response.setHeader("content-type", "application/octet-stream");
                response.setContentType("application/octet-stream");
                // 设置文件名
                response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));

                // 实现文件下载
                byte[] buffer = new byte[1024];
                FileInputStream fis = null;
                BufferedInputStream bis = null;
                try {
                    fis = new FileInputStream(file);
                    bis = new BufferedInputStream(fis);
                    OutputStream os = response.getOutputStream();
                    int i = bis.read(buffer);
                    while (i != -1) {
                        os.write(buffer, 0, i);
                        i = bis.read(buffer);
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    try {
                        if (bis != null) {
                            bis.close();
                        }
                        if (fis != null) {
                            fis.close();
                        }
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }
        }
    }

2.文件下载前端代码

<!DOCTYPE html>
<html lang="en"  xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../static/jquery-3.4.1.js"></script>
    <script>
       function download(e) {
           var data =$(e).prev().text();
           window.location.href = "/file/downloadFile?fileName="+data;
       }
    </script>
</head>
<body>
<p th:each="file:${fileList}">
    <a th:text="${file}" href="#"></a>
    <input type="button" value="下载" onclick="download(this)">
</p>
</body>
</html>

3.文件下载功能测试