SpringBoot项目 前后端分离 ajax附件上传下载

目录

前台界面 

上传 

下载 

前台代码

后台项目结构

后台主要代码

下载

调整对下载不存在文件的处理

效果

代码 

---

前台界面 

上传 

下载 

前台代码

    
    


    

    

        附件上传、下载
    

    

    文件：
    
    
    

    
    
    

后台项目结构

后台主要代码

package com.lxw.uploaddownload.controller;

import com.lxw.uploaddownload.common.Response;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.Date;

@RestController
@RequestMapping("/file")
public class FileController {

    @Value("${filePath}")
    private String filePath;

    private static final Logger logger = LoggerFactory.getLogger(FileController.class);

    //上传文件
    @PostMapping("/upload")
    @ResponseBody
    public Response uploadFile(@RequestParam("file") MultipartFile file, @RequestParam("fid") Integer fid, HttpServletResponse response)  {

        if (file.isEmpty()) {
            return new Response().error("上传失败，请选择文件");
        }
        // 获得提交的文件名
        String fileName = file.getOriginalFilename();
        // 获取文件输入流
        //InputStream ins = file.getInputStream();
        // 获取文件类型
        //String contentType = file.getContentType();

        //加个时间戳，尽量避免文件名称重复
        fileName = new SimpleDateFormat("yyyyMMddHHmmssSSSS").format(new Date()) + "_" + fileName;

        File dest = new File(filePath + fileName);
        if (!dest.getParentFile().exists()) { //判断文件父目录是否存在
            dest.getParentFile().mkdir();
        }
        try {
            file.transferTo(dest);
            //logger.info("上传成功");
            return new Response().success(fileName);
        } catch (Exception e) {
            //logger.error(e.getMessage());
            return new Response().error("上传失败");
        }
    }

    //下载文件
    @GetMapping(value = "/download")
    public void downloadFile(@RequestParam(name = "file_name") String fileName,
                             HttpServletRequest request,
                             HttpServletResponse response) throws IOException {
        //logger.info("download....file_name:" + fileName);

        File file = new File(filePath + "/" + fileName);
        if (file.exists()) { //判断文件是否存在
            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();
            }
            logger.info("----------file download" + fileName);
            try {
                bis.close();
                fis.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }else{
            response.setStatus(404);
        }
    }

}
 

package com.lxw.uploaddownload.controller;


import com.lxw.uploaddownload.common.Response;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.Date;

@RestController
@RequestMapping("/file")
public class FileController {

    @Value("${filePath}")
    private String filePath;

    private static final Logger logger = LoggerFactory.getLogger(FileController.class);


    //上传文件
    @PostMapping("/upload")
    @ResponseBody
    public Response uploadFile(@RequestParam("file") MultipartFile file, @RequestParam("fid") Integer fid, HttpServletResponse response)  {

        if (file.isEmpty()) {
            return new Response().error("上传失败，请选择文件");
        }
        // 获得提交的文件名
        String fileName = file.getOriginalFilename();
        // 获取文件输入流
        //InputStream ins = file.getInputStream();
        // 获取文件类型
        //String contentType = file.getContentType();

        //加个时间戳，尽量避免文件名称重复
        fileName = new SimpleDateFormat("yyyyMMddHHmmssSSSS").format(new Date()) + "_" + fileName;

        File dest = new File(filePath + fileName);
        if (!dest.getParentFile().exists()) { //判断文件父目录是否存在
            dest.getParentFile().mkdir();
        }
        try {
            file.transferTo(dest);
            //logger.info("上传成功");
            return new Response().success(fileName);
        } catch (Exception e) {
            //logger.error(e.getMessage());
            return new Response().error("上传失败");
        }
    }

    //下载文件
    @GetMapping(value = "/download")
    public void downloadFile(@RequestParam(name = "file_name") String fileName,
                             HttpServletRequest request,
                             HttpServletResponse response) throws IOException {
        //logger.info("download....file_name:" + fileName);

        File file = new File(filePath + "/" + fileName);
        if (file.exists()) { //判断文件是否存在
            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();
            }
            logger.info("----------file download" + fileName);
            try {
                bis.close();
                fis.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }else{
            response.setStatus(404);
        }
    }

}

下载

Demo下载

调整对下载不存在文件的处理

效果

代码 

        if (file.exists()) { //判断文件是否存在
             //
        } else {
            try {
                response.setContentType("text/html; charset=UTF-8"); //转码
                PrintWriter out = response.getWriter();
                out.flush();
                out.println("文件不存在或已经被删除！");
            } catch (IOException e) {
                // logger.error("下载文件出错:" + e);
            }
        }