Android SD卡-白红宇的个人博客

Android SD卡

发布日期：2021-05-10 11:49:34 浏览次数：12 分类：精选文章

本文共 3491 字，大约阅读时间需要 11 分钟。

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��Android��SD��mount�� ```java if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { Toast.makeText(MainActivity.this, "SD��", Toast.LENGTH_SHORT).show(); } else { Toast.makeText(MainActivity.this, "SD��", Toast.LENGTH_SHORT).show(); } ```

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��SD�� ```java File extStorage = Environment.getExternalStorageDirectory(); long usableSpace = extStorage.getUsableSpace(); long totalSpace = extStorage.getTotalSpace(); String usableSize = Formatter.formatFileSize(MainActivity.this, usableSpace); String totalSize = Formatter.formatFileSize(MainActivity.this, totalSpace); Toast.makeText(MainActivity.this, "��" + usableSize + "��" + totalSize, Toast.LENGTH_SHORT).show(); ```

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��Android6.0��API level 23��Canonical�� ```xml

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private static final int REQUEST_EXTERNAL_STORAGE = 1;  private static String[] PERMISSIONS_STORAGE = {      "android.permission.READ_EXTERNAL_STORAGE",      "android.permission.WRITE_EXTERNAL_STORAGE"  };  public static void verifyStoragePermissions(Activity activity) {      try {          int permission = ActivityCompat.checkSelfPermission(activity, "android.permission.WRITE_EXTERNAL_STORAGE");          if (permission != PackageManager.PERMISSION_GRANTED) {              ActivityCompat.requestPermissions(activity, PERMISSIONS_STORAGE, REQUEST_EXTERNAL_STORAGE);          }      } catch (Exception e) {          e.printStackTrace();      }  }

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��SD�� ```java File file = new File(extStorage, "test.txt"); try { verifyStoragePermissions(MainActivity.this); OutputStream out = new FileOutputStream(file); out.write("��!".getBytes()); out.close(); } catch (Exception e) { e.printStackTrace(); } ```

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File file = new File(extStorage, "test.txt");  try {      InputStream in = new FileInputStream(file);      byte[] buffer = new byte[64];      int len = in.read(buffer);      String content = new String(buffer, 0, len);      Toast.makeText(MainActivity.this, "���������������" + content, Toast.LENGTH_SHORT).show();  } catch (Exception e) {      e.printStackTrace();  }

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��shell��`cp`�� ```bash sudo cp /path/to/source /mnt/external/destination/ ``` ��`tr`��`awk`�� ```bash find /mnt/external/ -name "*.log" -type f -exec mv -t /mnt/backup/ {} \; ```

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