spring MVC文件上传

1、首先，在pom.xml文件中添加相关依赖

<dependency>
      <groupId>commons-io</groupId>
      <artifactId>commons-io</artifactId>
      <version>2.3</version>
    </dependency>
    <dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>1.3.2</version>
    </dependency>      

2、在spring mvc配置文件中增加一个文件上传bean 

<!-- SpringMVC上传文件时，需要配置MultipartResolver处理器 -->
    <bean id="multipartResolver"
     　　class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8" />
    </bean>      

 3、contruller代码文件

import org.apache.commons.io.FileUtils;
import org.springframework.stereotype.Controller;
import org.springframework.util.ResourceUtils;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.io.IOException;
import java.util.List;

/**
 * @author lenovo
 */
@Controller
public class UploadDemoController {/**
     * 上传单个文件
     * 通过MultipartFile读取文件信息，如果文件为空跳转到结果页并给出提示；
     * 如果不为空读取文件流并写入到指定目录，最后将结果展示到页面
     * @param origFile
     * @param
     * @return
     */
    @RequestMapping("/upload")
    public String uploadSingleFile(@RequestParam("file") MultipartFile origFile,HttpServletRequest request
                         ) {
        
        if (origFile.isEmpty()) {
            //redirectAttributes.addFlashAttribute("message", "Please select a file to upload");
            return "upload_result";
        }

        try {
             String contentType = origFile.getContentType();
             String fileName = origFile.getOriginalFilename();
             byte[] bytes = origFile.getBytes();
             System.out.println("上传文件名为-->" + fileName);
             System.out.println("上传文件类型为-->" + contentType);
             System.out.println("上传文件大小为-->"+bytes.length);
             
             String filePath=ResourceUtils.getURL("classpath:").getPath();
             File parentPath = new File(filePath,"imgupload");
             System.out.println("上传目的地为-->"+parentPath.getAbsolutePath());
             try {
                 //上传目的地
                 File destFile = new File(parentPath, fileName);
                 FileUtils.writeByteArrayToFile(destFile,origFile.getBytes());
             } catch (Exception e) {
                 // TODO: handle exception
             }

           　request.setAttribute("message",  "You successfully uploaded '" + origFile.getOriginalFilename() + "'");
        } catch (IOException e) {
            e.printStackTrace();
        }

        return "upload_result";
    }
    
    /**
     * 上传多个文件，同时接受业务数据
     * @param origFiles
     * @param request
     * @param user
     * @return
     */
    @RequestMapping("/uploadMultiFiles")
    public String uploadMultiFiles(@RequestParam("file") List<MultipartFile> origFiles,HttpServletRequest request
               ,User user           ) {
        
        System.out.println("User=="+user);
        if (origFiles.isEmpty()) {
            return "upload_result";
        }

        try {
            for (MultipartFile origFile : origFiles) {
                 String contentType = origFile.getContentType();
                 String fileName = origFile.getOriginalFilename();
                 byte[] bytes = origFile.getBytes();
                 System.out.println("上传文件名为-->" + fileName);
                 System.out.println("上传文件类型为-->" + contentType);
                 System.out.println("上传文件大小为-->"+bytes.length);
                 

                 String filePath = "f:/myres";

                 System.out.println("上传目的地为-->"+filePath);
                 try {
                     File destFile = new File(filePath,fileName);//上传目的地
                     FileUtils.writeByteArrayToFile(destFile,origFile.getBytes());
                 } catch (Exception e) {
                     // TODO: handle exception
                 }

            }
            
           　request.setAttribute("message",  "You successfully uploaded ");
        } catch (IOException e) {
            e.printStackTrace();
        }

        return "upload_result";
    }
}      

 4、前端页面代码

　上传页面

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<h1>Spring Boot file upload example</h1>

<!-- 上传单个对象 注意表单的method属性设为post,enctype属性设为multipart/form-data -->
<form method="POST" action="/upload" enctype="multipart/form-data">
    <input type="file" name="file" /><br/><br/>
    <input type="submit" value="上传" />
</form>

<!-- 上传多个对象 注意表单的method属性设为post,enctype属性设为multipart/form-data -->
<form method="POST" action="/uploadMultiFiles" enctype="multipart/form-data">
   <p>文件1：<input type="file" name="file" /></p>
     <p>文件2：<input type="file" name="file" /></p>
    <p>文件3：<input type="file" name="file" /></p>
    <!-- 同时传递其他业务字段 -->
    <p>用户名：<input type="text" name="userName" /></p>
    <p>年龄：<input type="text" name="age" /></p>
    <p><input type="submit" value="上传" /></p>
</form>
</body>
</html>      

　　结果页面

<%@ 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>Insert title here</title>
</head>
<body>
    <h2>上传结果为：${message}</h2>
    
       <img alt="图片不能显示" src="/myres/QQ图片20190222180514.png"/>
</body>
</html>      

 注：图片显示需要配置相关映射

<Context docBase="f:/myres" path="/myres"/>

意思就是当访问相对路径path时，就会自动自动访问dobase路径下的文件

具体设置参见：https://blog.csdn.net/Sunmeok/article/details/81477585

转载于:https://www.cnblogs.com/jeat/p/10431880.html