从文件夹

Question

我正在尝试编写一个程序来从文件夹中读取每个文件，并且在读取文件中的内容后，该文件应该被删除。我可以编写程序来从文件夹中读取文件并分别从文件夹中删除文件，但是无法将它们集成到一个程序中。

Answer 1

您可以使用以下方法：

 public static void listFilesForFolder(File folder) {
     for (final File fileEntry : folder.listFiles()) {

        try {

            File newFile = new File(fileEntry.getName()));

            /*read the newFile whatever way you want to*/

           /* then after reading delete it */

            if(newFile.delete()){
              System.out.println("File is deleted");
            }else {
              System.out.println("Could not delete file");
            };


        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }


        }
    }

您可以按以下方式输入文件夹名称：

文件newFile = new File（＆＃34; C：// path // to // file //＆＃34; + fileEntry.getName（））;

Answer 2

这是我编写和测试的Java代码。它工作正常。

它将首先列出指定目录中的所有文件以及其中所有级别的子目录。

然后它将读取指定目录中的所有文件＆amp;其中的所有级别的子目录都是一个接一个，然后在读完文件后删除它们。

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;

public class RecursiveFileDisplay {

    public static void main(String[] args) {
        File currentDir = new File("D:\\test"); // current directory
        File[] fileList = displayDirectoryContents(currentDir);
        readAndDeleteFiles(fileList);
    }

    public static File[] displayDirectoryContents(File dir) {
        File[] files = null;
        try {
            files = dir.listFiles();
            for (File file : files) {
                if (file.isDirectory()) {
                    System.out.println("directory:" + file.getCanonicalPath());
                    //recursive call to fetch file list in all levels of sub-directories
                    displayDirectoryContents(file); 
                } else {
                    System.out.println("     file:" + file.getCanonicalPath());
                }
            }

        } catch (IOException e) {
            e.printStackTrace();
        }
        return files;
    }
    public static void readAndDeleteFiles(File[] fileList){
        BufferedReader br = null;
        for(File file : fileList){
            if (!file.isDirectory()){
                try {

                    String sCurrentLine;

                    br = new BufferedReader(new FileReader(file.getCanonicalPath()));
                    if (br != null){
                        System.out.println("Reading file : " + file.getCanonicalPath());

                        while ((sCurrentLine = br.readLine()) != null) {
                            System.out.println(sCurrentLine);
                        }

                        br.close();
                        System.out.println("Finished reading file : " + file.getCanonicalPath());
                    }

                    //deleting file
                    if(file.delete()){
                        System.out.println(file.getCanonicalPath() + " is deleted!");
                    }
                    else{
                        System.out.println(file.getCanonicalPath() + " could not be deleted!"); 
                    }

                } catch (IOException e) {
                    e.printStackTrace();
                }

            }
            else{
                //recursive call to fetch file list in all levels of sub-directories and then read & delete each of them
                readAndDeleteFiles(file.listFiles());
            }
        }
    }

}