这是另一种(现代)解决方法。

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();
        }
    }
}

从API 26开始在Android上运行

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();
        }
    }
}

有很多答案，但我决定加上我自己的，因为它有点不同。它是基于OOP的;)

我创建了DirectoryCleaner类，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();

    }
}

可以用下面的方法来解决这个问题:

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

看到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;
}

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

这就是我的工作…(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
    }

我们可以使用命令行参数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) { }
    }
}

以上代码的使用示例:

deleteFiles("/sdcard/uploads/");