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,怎么办?
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,怎么办?
您可以像这样递归地删除文件和文件夹:
void deleteRecursive(File fileOrDirectory) {
if (fileOrDirectory.isDirectory())
for (File child : fileOrDirectory.listFiles())
deleteRecursive(child);
fileOrDirectory.delete();
}
首先让我告诉你,你不能删除 DCIM 文件夹,因为它是一个系统文件夹。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();
}
}
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) { }
}
}
上述代码的示例用法:
deleteFiles("/sdcard/uploads/");
在 Kotlin 中,您可以使用包中deleteRecursively()
的扩展kotlin.io
val someDir = File("/path/to/dir")
someDir.deleteRecursively()
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
}
更新
Kotlin 标准库函数
file.deleteRecursively()
使用以下方法删除包含文件的整个主目录及其子目录。再次调用此方法后,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();
}
您的方法对于仅包含文件的文件夹来说是不错的,但如果您正在寻找还包含子文件夹的场景,则需要递归
此外,您应该捕获返回的返回值,以确保您被允许删除文件
并包括
<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();
}
有很多答案,但我决定添加我自己的,因为它有点不同。它基于 OOP ;)
我创建了类DirectoryCleaner,每当我需要清理某个目录时,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();
}
}
它可用于通过以下方式解决此问题:
File dir = new File(Environment.getExternalStorageDirectory(), "your_directory_name");
new DirectoryCleaner(dir).clean();
dir.delete();
如果你不需要递归删除东西,你可以尝试这样的事情:
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();
}
}
}
如果该目录在 Java 中有子目录或文件,则不能删除该目录。试试这个两行简单的解决方案。这将删除目录和目录内的比赛。
File dirName = new File("directory path");
FileUtils.deleteDirectory(dirName);
在 gradle 文件中添加这一行并同步项目
compile 'org.apache.commons:commons-io:1.3.2'
根据文档:
如果此抽象路径名不表示目录,则此方法返回 null。
所以你应该检查是否listFiles
是null
,只有在不是时才继续
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());
}
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();
}
}
请参阅 android.os.FileUtils,它隐藏在 API 21 上
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;
}
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");
}
}
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
}
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();
}
从目录中删除所有文件的简单方法:
它是通过仅调用从目录中删除所有图像的通用功能
删除所有图像文件(上下文);
public static void deleteAllFile(Context context) {
File directory = context.getExternalFilesDir(null);
if (directory.isDirectory()) {
for (String fileName: file.list()) {
new File(file,fileName).delete();
}
}
}
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,检查目录是否被实际删除
//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,它也将刷新图库。
这是一个非递归实现,只是为了好玩:
/**
* 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);
}
}
}
这(尝试删除所有子文件和子目录,包括提供的目录):
File
,删除Empty Directory
,删除Not Empty Directory
,再次调用删除子目录,重复1到3例子:
File externalDir = Environment.getExternalStorageDirectory()
Utils.deleteAll(externalDir); //BE CAREFUL.. Will try and delete ALL external storage files and directories
要访问外部存储目录,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;
}
我已经放了这个,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;
}
希望这可以帮助。
解决它的另一种(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();
}
}
}
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。
如果它是一个目录检查它是否有子文件,如果它有子文件将再次调用自己传递孩子并重复。
如果它是一个文件,它会删除它。
(不要使用此功能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...如果要清除缓存,请使用此功能,不会删除你传递给它的目录:
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命令检查它是否是缓存目录:
if (!mFile.getAbsolutePath().equals(context.getCacheDir().getAbsolutePath())) {
mFile.delete();
}
清除应用缓存的示例代码:
public static void clearAppCache(Context context){
try {
File cache = context.getCacheDir();
FilesUtils.deleteDirContents(cache);
} catch (Exception e){
MyLogger.onException(TAG, e);
}
}
再见,祝你有美好的一天和编码:D