springmvc中文件的上传和下载

文件的下载

导入springmvc依赖
将tomcat的jar包加入model的依赖中

下载代码

@RequestMapping("/fileDownload")
public String fileDownload(HttpServletRequest request, HttpServletResponse response) throws Exception {
    // 获得当前项目路径下的下载文件（真实开发中文件名肯定是从数据中读取的）
    String realPath = request.getServletContext().getRealPath("/file/20181129204254948.png");
    File file = new File(realPath);
    String fileName = file.getName();
    // 设置响应头 content-disposition： 就是设置文件下载的打开方式，默认会在网页上打开，
    // 设置attachment;filename= 就是为了以下载方式来打开文件
    // "UTF-8"设置如果文件名有中文就不会乱码
    response.setHeader("content-disposition", "attachment;filename="+ URLEncoder.encode(fileName, "UTF-8"));
    InputStream in = new FileInputStream(realPath);
    int len = 0;
    byte[] buffer = new byte[1024];
    OutputStream out = response.getOutputStream();
    while ((len=in.read(buffer))>0){
        out.write(buffer,0,len);
    }
    in.close();
    return null;
}
/**
     * 基于spring ResponseEntity的文件下载 不支持缓冲区
     * ResponseEntity 可以同时定制文件的响应内容，响应头， 响应状态码
     */
@RequestMapping("/responseBody")
public ResponseEntity<String> responseBody(){
    String body = "Hello wuJiao";
    HttpHeaders httpHeaders = new HttpHeaders();
    httpHeaders.set("Set-Cookie","name=jqc");
    return new ResponseEntity<String>(body,httpHeaders, HttpStatus.OK);
}

文件的上传

导入springmvc依赖和上传特有依赖

<!--1.加入依赖-->
<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.2.6.RELEASE</version>
</dependency>
<!--基于Jakarta commons-fileupload的上传支持-->
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.4</version>
</dependency>

将jar包手动加入到tomcat容器中

注入文件上传解析器

<!--基于CommonsMultipartResolver的文件上传解析器-->
<bean class="org.springframework.web.multipart.commons.CommonsMultipartResolver" name="multipartResolver">
    <property name="maxUploadSize" value="#{1024*1024*10}"></property>
    <property name="defaultEncoding" value="UTF-8"></property>
</bean>

上传form表单要加上enctype="multipart/form-data"，选择多文件input属性加multiple

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
  <head>
    <title>$Title$</title>
  </head>
  <body>
   
  <a href="${pageContext.request.contextPath}/download">文件下载</a>

   <form enctype="multipart/form-data" action="${pageContext.request.contextPath}/upload01" method="post">
     <p>文件描述：<input type="text" name="desc" /></p>
     <p>文件：<input type="file" name="myfile" multiple accept="image/*"/></p>
     <p><input type="submit" value="上传单个文件"></p>
   </form>
   <hr>
  <form enctype="multipart/form-data" action="${pageContext.request.contextPath}/upload03" method="post">
    <p>文件描述：<input type="text" name="desc" /></p>
    <p>文件：<input type="file" name="myfile" multiple accept="image/*"/></p>
    <p><input type="submit" value="上传多个文件"></p>
  </form>

  </body>
</html>

后台代码

 /**
     *基于springmvc MultiPartResolver文件上传
     * @param desc
     * @param myFile
     * @param model
     * @return
     * @throws IOException
     */
@PostMapping("/upload01")
public String upload01(String desc,@RequestParam MultipartFile myFile, Model model) throws IOException {
    String path = "D:\\test\\"+ myFile.getOriginalFilename();
    File file = new File(path);
    //上传文件
    myFile.transferTo(file);
    model.addAttribute("filename",myFile.getOriginalFilename());
    return "success";
}

/**
     * 多文件上传
     * @param desc
     * @param myFile
     * @return
     * @throws IOException
     */
@PostMapping("/upload02")
public String upload02(String desc,@RequestParam MultipartFile[] myFile) throws  IOException {
    for (MultipartFile multipartFile : myFile) {
        String path = "D:\\test\\"+multipartFile.getOriginalFilename();
        File file = new File(path);
        //上传文件
        multipartFile.transferTo(file);
    }
    return "success";
}

posted @ 2021-03-21 21:51 阿灿呀阅读(62) 评论(0) 收藏举报

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springmvc中文件的上传和下载

文件的下载

文件的上传

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