SSM网页下载文件

快来打我* 2024-02-19 15:52 49阅读 0赞

效果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0RHSDI0MzAyODQ4MTc_size_16_color_FFFFFF_t_70][]

需要的资源：

commons-fileupload-1.3.1.jar，commons-io-1.3.2.jar

步骤：

1：搭建SSM框架：

2：在配置文件springconfig.xml中添加配置

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            
            <property name="defaultEncoding" value="UTF-8" />
            
            <property name="maxUploadSize" value="5242880" />
            <property name="maxInMemorySize" value="4096" />
        </bean>

3：编写下载jsp文件：download.jsp

<%@ 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>下载文件</title>
    </head>
    <body>
    <h1>文件下载实例</h1>
    	<form action="${pageContext.request.contextPath}/download.action" method="get">
    		<input type="submit" value="下载">
    	</form>
    </body>
    </html>

4：编辑控制器：

/**
       * 文件下载功能
       * @param request
       * @param response
       * @throws Exception
       */
      @RequestMapping("/download")
      @ResponseBody
      public String down(HttpServletRequest request,HttpServletResponse response) throws Exception{
          //模拟文件，myfile.txt为需要下载的文件
          String fileName = request.getSession().getServletContext().getRealPath("upload")+"/myfile.txt";
          //获取输入流
          InputStream bis = new BufferedInputStream(new FileInputStream(new File(fileName)));
          //假如以中文名下载的话
          String filename = "下载文件.txt";
          //转码，免得文件名中文乱码
          filename = URLEncoder.encode(filename,"UTF-8");
          //设置文件下载头
          response.addHeader("Content-Disposition", "attachment;filename=" + filename);  
          //1.设置文件ContentType类型，这样设置，会自动判断下载文件类型  
          response.setContentType("multipart/form-data"); 
          BufferedOutputStream out = new BufferedOutputStream(response.getOutputStream());
          int len = 0;
          while((len = bis.read()) != -1){
              out.write(len);
              out.flush();
          }
          out.close();
          return "login2";
      }

5：运行，成功的话页面信息如下，点击下载看是否能正常下载：

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L0RHSDI0MzAyODQ4MTc_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/88f04a0ea59646c1829a085de879f65a.png