126.文件下載是在版本2的基礎上完成的

時間 2019-11-18

標籤文件下載版本基礎上完成简体版

原文原文鏈接

1.效果

2. 後臺

2.1 實體類加兩個屬性

上傳的時候保存屬性html

2.2 頁面

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>文件下載</title>
   <style>
   .expa{ width:120px; height:80px; border:1px solid #F00}
   .expb{ width:200px; height:120px; border:1px solid #00F}
   </style>
</head>
<body>
   <h3>文件下載</h3>
   <div>
       <img alt="" src="${requestScope.user.filepath}" width="400px" height="300px">
   </div>
<a href="${pageContext.request.contextPath }/download.action?filename=${requestScope.user.realname}">
   ${requestScope.user.image.originalFilename }
   </a>
</body>
</html>java

2.3 後臺代碼

   /**
   * 6. 下載文件
   * @param request
   * @param filename
   * @param model
   * @return
   * @throws Exception
   */

   @RequestMapping(value="/download.action")
   public ResponseEntity<byte[]> download(HttpServletRequest request, @RequestParam("filename") String filename, Model model)throws Exception {
   //下載文件路徑
   // String path = request.getServletContext().getRealPath("/images/");
       String temp =request.getServletContext().getContextPath();
           String path = "D:/workspace"+temp+"/src/main/webapp/img";

   File file = new File(path + File.separator + filename);

   HttpHeaders headers = new HttpHeaders();
   //下載顯示的文件名，解決中文名稱亂碼問題
   String downloadFielName = new String(filename.getBytes("UTF-8"),"iso-8859-1");
   //通知瀏覽器以attachment（下載方式）打開圖片
   headers.setContentDispositionFormData("attachment", downloadFielName);
   //application/octet-stream ：二進制流數據（最多見的文件下載）。
   headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);// MediaType 用spring框架的
   return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), // FileUtils 選擇 org.apache.commons.io.FileUtils
   headers, HttpStatus.CREATED);
   }web