springBoot实现上传下载使用的是thymeleaf模板插件
1.在pom.xml中添加配置文件的
<!-- thymeleaf模板插件 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<!-- devtools插件，热部署 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
<scope>true</scope>
</dependency>
2.在springBoot中添加thymeleaf的配置
#配置thymeleaf的模板模式为HTML5
spring.thymeleaf.mode= HTML5
3.在启动类中配置一个文件上传大小的类
package com.seecen;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.MultipartConfigFactory;
import org.springframework.context.annotation.Bean;
import javax.servlet.MultipartConfigElement;
@MapperScan({"com.seecen.dao","com.seecen.mapper"})
@SpringBootApplication
public class SpringbootdemoApplication {
public static void main(String[] args) {
SpringApplication.run(SpringbootdemoApplication.class, args);
}
/**
* 文件上传配置
* @return
*/
@Bean
public MultipartConfigElement multipartConfigElement() {
MultipartConfigFactory factory = new MultipartConfigFactory();
//单个文件最大
factory.setMaxFileSize("10240KB"); //KB,MB
/// 设置总上传数据总大小
factory.setMaxRequestSize("102400KB");
return factory.createMultipartConfig();
}
}
4.Controller类上传下载实现方法
package com.seecen.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.List;
@Controller
public class FileController {
/**
* 实现文件上传
* */
@RequestMapping("file")
public String file(@RequestParam("fileName") MultipartFile file,HttpServletResponse response){
if(file.isEmpty()){
return "Exception";
}
String fileName = file.getOriginalFilename();
int size = (int) file.getSize();
System.out.println(fileName + "--" + size);
String path = "F:/file" ;
File dest = new File(path + "/" + fileName);
if(!dest.getParentFile().exists()){ //判断文件父目录是否存在
dest.getParentFile().mkdir();
}
try {
file.transferTo(dest); //保存文件
System.out.println("上传成功");
return "index2";
} catch (IllegalStateException e) {
e.printStackTrace();
return "Exception";
} catch (IOException e) {
e.printStackTrace();
return "Exception";
}
}
/**
* 实现多文件上传
* */
@RequestMapping(value="morefile",method= RequestMethod.POST)
/**public @ResponseBody String multifileUpload(@RequestParam("fileName")List<MultipartFile> files) */
public String multifileUpload(HttpServletRequest request){
List<MultipartFile> files = ((MultipartHttpServletRequest)request).getFiles("fileName");
if(files.isEmpty()){
return "Exception";
}
String path = "F:/file" ;
for(MultipartFile file:files){
String fileName = file.getOriginalFilename();
int size = (int) file.getSize();
System.out.println(fileName + "--" + size);
if(file.isEmpty()){
return "Exception";
}else{
File dest = new File(path + "/" + fileName);
if(!dest.getParentFile().exists()){ //判断文件父目录是否存在
dest.getParentFile().mkdir();
}
try {
file.transferTo(dest);
}catch (Exception e) {
e.printStackTrace();
return "Exception";
}
}
}
return "index2";
}
/*
*文件下载
*/
@RequestMapping("download")
public String downLoad(HttpServletResponse response){
String filename="2.jpg";
String filePath = "文件" ;
File file = new File(filePath + "/" + filename);
if(file.exists()){ //判断文件父目录是否存在
response.setContentType("application/force-download");
response.setHeader("Content-Disposition", "attachment;fileName=" + filename);
byte[] buffer = new byte[1024];
FileInputStream fis = null; //文件输入流
BufferedInputStream bis = null;
OutputStream os = null; //输出流
try {
os = response.getOutputStream();
fis = new FileInputStream(file);
bis = new BufferedInputStream(fis);
int i = bis.read(buffer);
while(i != -1){
os.write(buffer);
i = bis.read(buffer);
}
} catch (Exception e) {
e.printStackTrace();
}
System.out.println("----------file download" + filename);
try {
bis.close();
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
}
5.上传下载页面
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org"
xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity3">
<head>
<meta charset="UTF-8" />
<title>Insert title here</title>
</head>
<body>
<h1 th:inlines="text">文件上传</h1>
<form action="file" method="post" enctype="multipart/form-data">
<p>选择文件: <input type="file" name="fileName"/></p>
<p><input type="submit" value="提交"/></p>
</form>
</body>
</html>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org"
xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity3">
<head>
<meta charset="UTF-8" />
<title>Insert title here</title>
</head>
<body>
<h1 th:inlines="text">文件上传</h1>
<form action="morefile" method="post" enctype="multipart/form-data" >
<p>选择文件1: <input type="file" name="fileName"/></p>
<p>选择文件2: <input type="file" name="fileName"/></p>
<p>选择文件3: <input type="file" name="fileName"/></p>
<p><input type="submit" value="提交"/></p>
</form>
</body>
</html>
6.上传成功后进入index页面
注意配置文件中的spring.thymeleaf.prefix=classpath:/templates/表示扫描templates包下的html文件 默认就是扫描templates包下
所以页面需要放在templates下
thymeleaf基本语法教程
https://www.e-learn.cn/thymeleaf