如何删除整个文件夹和内容？

Question

我希望我的应用程序的用户能够删除 DCIM 文件夹（位于 SD 卡上并包含子文件夹）。

这可能吗，如果可以的话怎么办？

Answer 1

我已经把这个放了，尽管它会删除具有任何目录结构的文件夹。

public int removeDirectory(final File folder) {

    if(folder.isDirectory() == true) {
        File[] folderContents = folder.listFiles();
        int deletedFiles = 0;

        if(folderContents.length == 0) {
            if(folder.delete()) {
                deletedFiles++;
                return deletedFiles;
            }
        }
        else if(folderContents.length > 0) {

            do {

                File lastFolder = folder;
                File[] lastFolderContents = lastFolder.listFiles();

                //This while loop finds the deepest path that does not contain any other folders
                do {

                    for(File file : lastFolderContents) {

                        if(file.isDirectory()) {
                            lastFolder = file;
                            lastFolderContents = file.listFiles();
                            break;
                        }
                        else {

                            if(file.delete()) {
                                deletedFiles++;
                            }
                            else {
                                break;
                            }

                        }//End if(file.isDirectory())

                    }//End for(File file : folderContents)

                } while(lastFolder.delete() == false);

                deletedFiles++;
                if(folder.exists() == false) {return deletedFiles;}

            } while(folder.exists());
        }
    }
    else {
        return -1;
    }

    return 0;

}

希望这有帮助。

Answer 2

解决这个问题的另一种（现代）方法。

public class FileUtils {
    public static void delete(File fileOrDirectory) {
        if(fileOrDirectory != null && fileOrDirectory.exists()) {
            if(fileOrDirectory.isDirectory() && fileOrDirectory.listFiles() != null) {      
                Arrays.stream(fileOrDirectory.listFiles())
                      .forEach(FileUtils::delete);
            }
            fileOrDirectory.delete();
        }
    }
}

自 API 26 起在 Android 上

public class FileUtils {

    public static void delete(File fileOrDirectory)  {
        if(fileOrDirectory != null) {
            delete(fileOrDirectory.toPath());
        }
    }

    public static void delete(Path path)  {
        try {
            if(Files.exists(path)) {
                Files.walk(path)
                        .sorted(Comparator.reverseOrder())
                        .map(Path::toFile)
//                      .peek(System.out::println)
                        .forEach(File::delete);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Answer 3

我正在使用这个递归函数来完成这项工作：

public static void deleteDirAndContents(@NonNull File mFile){
    if (mFile.isDirectory() && mFile.listFiles() != null && mFile.listFiles().length > 0x0) {
        for (File file : mFile.listFiles()) {
            deleteDirAndContents(file);
        }
    } else {
        mFile.delete();
    }
}

该函数检查它是目录还是文件。

如果它是一个目录，则检查它是否有子文件，如果有子文件，将再次调用自己传递子文件并重复。

如果它是一个文件，则将其删除。

（不要使用此函数通过传递缓存目录来清除应用程序缓存，因为它也会删除缓存目录，因此应用程序将崩溃......
如果您想清除缓存，请使用此函数，该函数不会删除您传递给它的目录：

public static void deleteDirContents(@NonNull File mFile){
        if (mFile.isDirectory() && mFile.listFiles() != null && mFile.listFiles().length > 0x0) {
            for (File file : mFile.listFiles()) {
                deleteDirAndContents(file);
            }
        }
    }

或者您可以使用以下方法检查它是否是缓存目录：

if (!mFile.getAbsolutePath().equals(context.getCacheDir().getAbsolutePath())) {
    mFile.delete();
}

清除应用程序缓存的示例代码：

public static void clearAppCache(Context context){
        try {
            File cache = context.getCacheDir();
            FilesUtils.deleteDirContents(cache);
        } catch (Exception e){
            MyLogger.onException(TAG, e);
        }
    }

再见，祝您有美好的一天&编码：D

Answer 4

这是 kotlin 选项。效果非常好。

fun executeDelete(context: Context, paths: List<String>): Int {
    return try {
        val files = paths.map { File(it) }
        val fileCommands = files.joinToString(separator = " ") {
            if (it.isDirectory) "'${it.absolutePath}/'" else "'${it.absolutePath}'"
        }
        val command = "rm -rf $fileCommands"
        val process = Runtime.getRuntime().exec(arrayOf("sh", "-c", command))
        val result = process.waitFor()
        if (result == 0) {
            context.rescanPaths(paths)
        }
        result
    } catch (e: Exception) {
        -1
    }
}

// 避免连续多次调用此函数，它可以删除整个文件夹内容

fun Context.rescanPaths(paths: List<String>, callback: (() -> Unit)? = null) {
if (paths.isEmpty()) {
    callback?.invoke()
    return
}

var cnt = paths.size
MediaScannerConnection.scanFile(applicationContext, paths.toTypedArray(), null) { _, _ ->
    if (--cnt == 0) {
        callback?.invoke()
    }
}
}

Answer 5

您可以像这样递归删除文件和文件夹：

void deleteRecursive(File fileOrDirectory) {
    if (fileOrDirectory.isDirectory())
        for (File child : fileOrDirectory.listFiles())
            deleteRecursive(child);

    fileOrDirectory.delete();
}

Answer 6

首先我告诉您，您无法删除 DCIM 文件夹，因为它是系统文件夹。当您在手机上手动删除它时，它将删除该文件夹的内容，但不会删除 DCIM 文件夹。您可以使用以下方法删除其内容：

根据评论更新

File dir = new File(Environment.getExternalStorageDirectory()+"Dir_name_here"); 
if (dir.isDirectory()) 
{
    String[] children = dir.list();
    for (int i = 0; i < children.length; i++)
    {
       new File(dir, children[i]).delete();
    }
}

Answer 7

我们可以使用命令行参数来删除整个文件夹及其内容。

public static void deleteFiles(String path) {

    File file = new File(path);

    if (file.exists()) {
        String deleteCmd = "rm -r " + path;
        Runtime runtime = Runtime.getRuntime();
        try {
            runtime.exec(deleteCmd);
        } catch (IOException e) { }
    }
}

上述代码的用法示例：

deleteFiles("/sdcard/uploads/");

Answer 8

在 Kotlin 中，您可以使用 kotlin.io 包中的 deleteRecursively() 扩展

val someDir = File("/path/to/dir")
someDir.deleteRecursively()

Answer 9

简短的 koltin 版本

fun File.deleteDirectory(): Boolean {
    return if (exists()) {
        listFiles()?.forEach {
            if (it.isDirectory) {
                it.deleteDirectory()
            } else {
                it.delete()
            }
        }
        delete()
    } else false
}

UPDATE

Kotlin stdlib 函数

file.deleteRecursively()

Answer 10

使用以下方法删除包含文件及其子目录的整个主目录。调用此方法后，再次调用主目录的delete()目录。

// For to Delete the directory inside list of files and inner Directory
public static boolean deleteDir(File dir) {
    if (dir.isDirectory()) {
        String[] children = dir.list();
        for (int i=0; i<children.length; i++) {
            boolean success = deleteDir(new File(dir, children[i]));
            if (!success) {
                return false;
            }
        }
    }

    // The directory is now empty so delete it
    return dir.delete();
}

Answer 11

对于仅包含文件的文件夹，您的方法是不错的，但是如果您正在寻找还包含子文件夹的场景，则需要递归

此外，您还应该捕获返回的返回值，以确保允许您删除文件

并包含

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

在你的清单中

void DeleteRecursive(File dir)
{
    Log.d("DeleteRecursive", "DELETEPREVIOUS TOP" + dir.getPath());
    if (dir.isDirectory())
    {
        String[] children = dir.list();
        for (int i = 0; i < children.length; i++)
        {
            File temp = new File(dir, children[i]);
            if (temp.isDirectory())
            {
                Log.d("DeleteRecursive", "Recursive Call" + temp.getPath());
                DeleteRecursive(temp);
            }
            else
            {
                Log.d("DeleteRecursive", "Delete File" + temp.getPath());
                boolean b = temp.delete();
                if (b == false)
                {
                    Log.d("DeleteRecursive", "DELETE FAIL");
                }
            }
        }

    }
    dir.delete();
}

Answer 12

有很多答案，但我决定添加自己的答案，因为它有点不同。它基于 OOP ;)

我创建了 DirectoryCleaner 类，每次当我需要清理某些目录时它都会帮助我。

public class DirectoryCleaner {
    private final File mFile;

    public DirectoryCleaner(File file) {
        mFile = file;
    }

    public void clean() {
        if (null == mFile || !mFile.exists() || !mFile.isDirectory()) return;
        for (File file : mFile.listFiles()) {
            delete(file);
        }
    }

    private void delete(File file) {
        if (file.isDirectory()) {
            for (File child : file.listFiles()) {
                delete(child);
            }
        }
        file.delete();

    }
}

它可以通过以下方式解决这个问题：

File dir = new File(Environment.getExternalStorageDirectory(), "your_directory_name");
new DirectoryCleaner(dir).clean();
dir.delete();

Answer 13

如果该目录包含 Java 中的子目录或文件，则无法删除该目录。尝试这个两行简单的解决方案。这将删除该目录以及目录内的竞赛。

File dirName = new File("directory path");
FileUtils.deleteDirectory(dirName);

在 gradle 文件中添加此行并同步项目

compile 'org.apache.commons:commons-io:1.3.2'  

Answer 14

根据文档：

如果此抽象路径名不表示目录，则此方法返回 null。

因此，您应该检查 listFiles 是否为 null，如果不是则继续

boolean deleteDirectory(File path) {
    if(path.exists()) {
        File[] files = path.listFiles();
        if (files == null) {
            return false;
        }
        for (File file : files) {
            if (file.isDirectory()) {
                deleteDirectory(file);
            } else {
                boolean wasSuccessful = file.delete();
                if (wasSuccessful) {
                    Log.i("Deleted ", "successfully");
                }
            }
        }
    }
    return(path.delete());
}

Answer 15

如果您不需要递归删除内容，您可以尝试如下操作：

File file = new File(context.getExternalFilesDir(null), "");
    if (file != null && file.isDirectory()) {
        File[] files = file.listFiles();
        if(files != null) {
            for(File f : files) {   
                f.delete();
            }
        }
    }

Answer 16

public static void deleteDirectory( File dir )
{

    if ( dir.isDirectory() )
    {
        String [] children = dir.list();
        for ( int i = 0 ; i < children.length ; i ++ )
        {
         File child =    new File( dir , children[i] );
         if(child.isDirectory()){
             deleteDirectory( child );
             child.delete();
         }else{
             child.delete();

         }
        }
        dir.delete();
    }
}

Answer 17

请参阅 android.os.FileUtils，它隐藏在 API 21

public static boolean deleteContents(File dir) {
    File[] files = dir.listFiles();
    boolean success = true;
    if (files != null) {
        for (File file : files) {
            if (file.isDirectory()) {
                success &= deleteContents(file);
            }
            if (!file.delete()) {
                Log.w("Failed to delete " + file);
                success = false;
            }
        }
    }
    return success;
}

来源： https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/os/FileUtils.java#414

Answer 18

最快、最简单的方法：

public static boolean deleteFolder(File removableFolder) {
        File[] files = removableFolder.listFiles();
        if (files != null && files.length > 0) {
            for (File file : files) {
                boolean success;
                if (file.isDirectory())
                    success = deleteFolder(file);
                else success = file.delete();
                if (!success) return false;
            }
        }
        return removableFolder.delete();
}

Answer 19

这就是我所做的......（简洁且经过测试）

    ...
    deleteDir(new File(dir_to_be_deleted));
    ...

    // delete directory and contents
    void deleteDir(File file) { 
        if (file.isDirectory())
            for (String child : file.list())
                deleteDir(new File(file, child));
        file.delete();  // delete child file or empty directory
    }

Answer 20

private static void deleteRecursive(File dir)
{
    //Log.d("DeleteRecursive", "DELETEPREVIOUS TOP" + dir.getPath());
    if (dir.isDirectory())
    {
        String[] children = dir.list();
        for (int i = 0; i < children.length; i++)
        {
            File temp = new File(dir, children[i]);
            deleteRecursive(temp);
        }

    }

    if (dir.delete() == false)
    {
        Log.d("DeleteRecursive", "DELETE FAIL");
    }
}

Answer 21

从目录中删除所有文件的简单方法：

它是通过仅调用

deleteAllImageFile(context);从目录中删除所有图像的通用函数；

public static void deleteAllFile(Context context) {
File directory = context.getExternalFilesDir(null);
        if (directory.isDirectory()) {
            for (String fileName: file.list()) {
                new File(file,fileName).delete();
            }
        }    
    } 

Answer 22

我知道的最安全的代码：

private boolean recursiveRemove(File file) {
    if(file == null  || !file.exists()) {
        return false;
    }

    if(file.isDirectory()) {
        File[] list = file.listFiles();

        if(list != null) {

            for(File item : list) {
                recursiveRemove(item);
            }

        }
    }

    if(file.exists()) {
        file.delete();
    }

    return !file.exists();
}

检查文件是否存在，处理空值，检查目录是否确实被删除

Answer 23

//To delete all the files of a specific folder & subfolder
public static void deleteFiles(File directory, Context c) {
    try {
        for (File file : directory.listFiles()) {
            if (file.isFile()) {
                final ContentResolver contentResolver = c.getContentResolver();
                String canonicalPath;
                try {
                    canonicalPath = file.getCanonicalPath();
                } catch (IOException e) {
                    canonicalPath = file.getAbsolutePath();
                }
                final Uri uri = MediaStore.Files.getContentUri("external");
                final int result = contentResolver.delete(uri,
                        MediaStore.Files.FileColumns.DATA + "=?", new String[]{canonicalPath});
                if (result == 0) {
                    final String absolutePath = file.getAbsolutePath();
                    if (!absolutePath.equals(canonicalPath)) {
                        contentResolver.delete(uri,
                                MediaStore.Files.FileColumns.DATA + "=?", new String[]{absolutePath});
                    }
                }
                if (file.exists()) {
                    file.delete();
                    if (file.exists()) {
                        try {
                            file.getCanonicalFile().delete();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                        if (file.exists()) {
                            c.deleteFile(file.getName());
                        }
                    }
                }
            } else
                deleteFiles(file, c);
        }
    } catch (Exception e) {
    }
}

这是您的解决方案，它也会刷新图库。

Answer 24

此（尝试删除所有子文件和子目录，包括提供的目录）：

1. 如果文件，则删除
2. 如果空目录，
3. 则 删除非空目录，再次调用删除子目录，重复1到3

示例：

File externalDir = Environment.getExternalStorageDirectory()
Utils.deleteAll(externalDir); //BE CAREFUL.. Will try and delete ALL external storage files and directories

要获得对外部存储目录的访问权限，您需要以下权限：

（使用ContextCompat.checkSelfPermission 和 ActivityCompat.requestPermissions)

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

递归方法：

public static boolean deleteAll(File file) {
    if (file == null || !file.exists()) return false;

    boolean success = true;
    if (file.isDirectory()) {
        File[] files = file.listFiles();
        if (files != null && files.length > 0) {
            for (File f : files) {
                if (f.isDirectory()) {
                    success &= deleteAll(f);
                }
                if (!f.delete()) {
                    Log.w("deleteAll", "Failed to delete " + f);
                    success = false;
                }
            }
        } else {
            if (!file.delete()) {
                Log.w("deleteAll", "Failed to delete " + file);
                success = false;
            }
        }
    } else {
        if (!file.delete()) {
            Log.w("deleteAll", "Failed to delete " + file);
            success = false;
        }
    }
    return success;
}

Answer 25

这是一个非递归实现，仅供娱乐：

/**
 * Deletes the given folder and all its files / subfolders.
 * Is not implemented in a recursive way. The "Recursively" in the name stems from the filesystem command
 * @param root The folder to delete recursively
 */
public static void deleteRecursively(final File root) {
    LinkedList<File> deletionQueue = new LinkedList<>();
    deletionQueue.add(root);

    while(!deletionQueue.isEmpty()) {
        final File toDelete = deletionQueue.removeFirst();
        final File[] children = toDelete.listFiles();
        if(children == null || children.length == 0) {
            // This is either a file or an empty directory -> deletion possible
            toDelete.delete();
        } else {
            // Add the children before the folder because they have to be deleted first
            deletionQueue.addAll(Arrays.asList(children));
            // Add the folder again because we can't delete it yet.
            deletionQueue.addLast(toDelete);
        }
    }
}