Vue SpringBoot 文件操作、上傳、預覽和刪除

視頻演示: https://www.bilibili.com/video/BV1VK4y1s7b1/

需要完成以下步驟:

1. 創建工程並引入依賴包
   • spring-boot-starter-web
   • lombok
2. 對文件進行操作，上傳、預覽和刪除
3. 添加跨域功能
4. 前端使用VUE，前后端分離
5. 看不懂代碼，不建議下載
6. 可以參考另一文章,文件上傳采用Form方式(前后端不分離)

#FileUploadController.java

package com.example.spring.fileupload;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.io.Resource;
import org.springframework.core.io.UrlResource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.ResponseEntity;
import org.springframework.util.FileSystemUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder;

import java.io.IOException;
import java.net.MalformedURLException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.util.List;
import java.util.stream.Collectors;

@RestController
public class FileUploadController {

    //上傳文件路徑
    @Value("${file.base.director}")
    private String fileBaseDirector;
    private Path fileBasePath;

    @Autowired
    private void createDirectories(){
        try {
            Files.createDirectories(Paths.get(fileBaseDirector));
        } catch (IOException e) {
            e.printStackTrace();
        }
        this.fileBasePath = Path.of(fileBaseDirector);
    }


    @GetMapping("/loadAll")
    public ResponseEntity loadAll() throws IOException {
        List<FileObject> filesAll = Files.walk(fileBasePath,1)
                .filter(path -> !path.equals(fileBasePath))
                .map(path -> {
                    String url = MvcUriComponentsBuilder.fromMethodName(FileUploadController.class,"loadFile",path.getFileName().toString()).build().toString();
                    FileObject  fileObject = new FileObject(path.getFileName().toString(),url);
                    return fileObject;
                }).collect(Collectors.toList());
        return ResponseEntity.ok(filesAll);
    }


    @DeleteMapping("delete/{fileName}")
    public ResponseEntity deleteFile(@PathVariable String fileName){
        Path deletePath = fileBasePath.resolve(fileName);
        Boolean isDelete = Boolean.FALSE;
        try {
            isDelete = FileSystemUtils.deleteRecursively(deletePath);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return ResponseEntity.ok(isDelete);
    }
    

    @PostMapping("/upload")
    public ResponseEntity upload(@RequestParam("file") MultipartFile file){
        String fileName = StringUtils.cleanPath(file.getOriginalFilename());
        Path path = Path.of(fileBaseDirector + fileName);
        try {
            Files.copy(file.getInputStream(),path,StandardCopyOption.REPLACE_EXISTING);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return ResponseEntity.ok("OK");
    }


}