Question

这些程序用于上传多个文件和一个被选中的文件。

我已经完成了上传多个文件，现在我应该列出所有文件并从这些列表中删除一个文件。我能够在控制台中列出文件。但是，我的先生告诉我，这不是道路。

我的问题是如何列出这些文件并删除其中一个。

向我解释列出上传文件并选择一个文件并删除的概念。

控制器程序可以正常上传多个文件。

/*This is controller program*/

import java.io.File;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.Resource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder;

import com.javasampleapproach.uploadfile.storage.StorageService;

@Controller
public class UploadController {

    @Autowired
    StorageService storageService;

    List<String> files = new ArrayList<String>();
    final String directoryWindows ="E://temp";

    @GetMapping("/")
    public String listUploadedFiles(Model model)
    {
        return "uploadForm";
    }

    @PostMapping("/")
    public String handleFileUpload(@RequestParam("filefield") File fname,
                                   @RequestParam("file") MultipartFile file, 
                                   Model model) 
    {
        try
        {
            storageService.store(file);
            model.addAttribute("message", "You successfully uploaded " + file.getOriginalFilename() + "!");
            files.add(file.getOriginalFilename());

                String filename =fname.getName();

                System.out.println(filename);
                File folder=new File("E:\\temp\\"+filename+"\\");

                folder.mkdirs();
                System.out.println(folder);

                byte[] bytes = file.getBytes();
                Path path = Paths.get("E:\\temp\\"+filename+"\\"+ file.getOriginalFilename());
                Files.write(path, bytes);

                listFilesForFolder(directoryWindows);


        }
        catch (Exception e) 
        {
            model.addAttribute("message", "FAIL to upload " + file.getOriginalFilename() + "!");
        }
        return "uploadForm";
    }

    public void listFilesForFolder(String folder)
    {
        File directory=new File(folder);

        for (final File fileEntry : directory.listFiles()) 
        {
             System.out.println(fileEntry.getName());
        }
     }


    @GetMapping("/gellallfiles")
    public String getListFiles( //@RequestParam("name") File first,
                                Model model)
    {
        model.addAttribute("files",
                files.stream()
                        .map(fileName -> MvcUriComponentsBuilder
                                .fromMethodName(UploadController.class, "getFile", fileName).build().toString())
                        .collect(Collectors.toList()));
        model.addAttribute("totalFiles", "TotalFiles: " + files.size());
        //String filesnames =first.getName();
        //System.out.println("welcome"+filesnames);
        return "listFiles";



    }

    @GetMapping("/files/{filename:.+}")
    @ResponseBody
    public ResponseEntity<Resource> getFile(@PathVariable String filename) 
    {
        Resource file = storageService.loadFile(filename);
        return ResponseEntity.ok()
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + file.getFilename() + "\"")
                .body(file);
    }
}


/* This is html program*/

<html xmlns:th="http://www.thymeleaf.org">
<body>
    <h2>List All Uploaded Files</h2>
    <div>
        <ul>

            <li th:each="file : ${files}">
                <a th:href="${file}" th:text="${file}" />
            </li>
        </ul>
    </div>
    <div>
        Enter File to Delete:<input type="text" name="name" id="id"/><br></br>
        <input type="submit" value="delete" />
    </div>
    <div>
        <h3 th:text="${totalFiles}"/>
        <a href="/">Back to UploadForm!</a>
    </div>

</body>
</html>



[output][1]

/* This is how output is printed */
How can I list those files and select one among them and delete it.

  [1]: https://i.stack.imgur.com/RzLVQ.png

从上传的文件中删除文件

0 个答案: