SpringMVC-文件的上传与下载

刺骨的言语ヽ痛彻心扉 2022-02-16 17:11 298阅读 0赞

# 文件的上传与下载 #

## 一、文件的上传： ##

#### 1.创建项目： ####

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDUwMjgwNA_size_16_color_FFFFFF_t_70]

#### 2.导入所需的jar包： ####

![在这里插入图片描述][20190422200030880.png]

#### 3.设置页面表单： ####

<%@ 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="tsext/html; charset=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<form action="upload" method="post" enctype="multipart/form-data">
    		账号:<input type="text" name="name"><br>
    		图片：<input type="file" name="file1"><br>
    		<input type="submit" value="提交">
    	</form>
    </body>
    </html>

**表单提交方式必须是post方式提交，enctype必须是multipart/form-data**

#### 4.Controller中接收数据: ####

package com.sxt.controller;
    
    @Controller
    public class UserController {
    
    	@RequestMapping("/upload")
    	@ResponseBody
    	public void upload(String name, MultipartFile file1) throws Exception {
    		System.out.println(name + " " + file1.getOriginalFilename());
    		file1.transferTo(new File("d:/vc/" + file1.getOriginalFilename()));
    	}
    }

#### 5.XML配置文件： ####

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
    	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    	xmlns:context="http://www.springframework.org/schema/context"
    	xmlns:mvc="http://www.springframework.org/schema/mvc"
    	xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
    		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">
    	
    	
    	<context:component-scan base-package="com.sxt.controller"/>
    	
    	
    	<mvc:annotation-driven/>
    	
    	
    	<bean name="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    	</bean>
    </beans>

#### 6.实现： ####

![在这里插入图片描述][20190422200748289.png]  
![在这里插入图片描述][20190422200809901.png]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDUwMjgwNA_size_16_color_FFFFFF_t_70 1]

## 二、文件的下载： ##

### 1.方式一:基于ResponseEntity实现 ###

@RequestMapping("/download1")
    	public void download(HttpServletRequest request, HttpServletResponse response) throws IOException {
    		File file = new File("d:/vc/2.jpg");
    		InputStream in = new FileInputStream(file);
    		// 设置响应的头部信息
    		response.setCharacterEncoding("utf-8");
    		response.setContentType("multipart/form-data");
    		response.setHeader("Content-Disposition", "attachment;fileName="+file.getName() );
    
    		ServletOutputStream out = response.getOutputStream();
    		// 文件复制
    		int num = 0;
    		byte[] b = new byte[1024];
    		while ((num = in.read(b)) != -1) {
    			out.write(b, 0, num);
    		}
    		out.flush();
    		out.close();
    		in.close();
    	}

### 2.通用下载实现： ###

@RequestMapping("/download2")
    	public ResponseEntity<byte[]> download(HttpServletRequest request) throws IOException {
    	    // 需要下载的文件
    		File file = new File("d:/vc/2.jpg");
    	    byte[] body = null;
    	    InputStream is = new FileInputStream(file);
    	    body = new byte[is.available()];
    	    is.read(body);
    	    HttpHeaders headers = new HttpHeaders();
    	    headers.add("Content-Disposition", "attchement;filename=" + file.getName());
    	    HttpStatus statusCode = HttpStatus.OK;
    	    ResponseEntity<byte[]> entity = new ResponseEntity<byte[]>(body, headers, statusCode);
    	    return entity;
    	}

### 实现： ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDUwMjgwNA_size_16_color_FFFFFF_t_70 2]

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[20190422200030880.png]: /images/20220216/8672f477b97e4e1f99e96a66cef9c497.png
[20190422200748289.png]: /images/20220216/f094f5d232484bceb9f1978ca2e4dd4a.png
[20190422200809901.png]: /images/20220216/6413cfa579474b28bf48d412f2f7afc1.png
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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDUwMjgwNA_size_16_color_FFFFFF_t_70 2]: /images/20220216/03f14e5ff0a140e899bf214b89052683.png