android sd卡数据库读取
16lz
2021-01-23
先在 Manifest 里添加权限 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /> 然后在 mainActivity 添加方法
SQLiteDatabase db;private final String DATABASE_PATH = android.os.Environment.getExternalStorageDirectory().getAbsolutePath() + "/vote";private String DATABASE_FILENAME = "db_vote.db";// 初始化数据库private SQLiteDatabase openDatabase() {try {String databaseFilename = DATABASE_PATH + "/" + DATABASE_FILENAME;File dir = new File(DATABASE_PATH);if (!dir.exists())dir.mkdirs();if (!(new File(databaseFilename)).exists()) {InputStream is = getResources().openRawResource(R.raw.db_vote);FileOutputStream fos = new FileOutputStream(databaseFilename);byte[] buffer = new byte[8192];int count = 0;while ((count = is.read(buffer)) > 0) {fos.write(buffer, 0, count);}fos.close();is.close();}db = SQLiteDatabase.openOrCreateDatabase(databaseFilename, null);return db;} catch (Exception e) {e.printStackTrace();}return null;} 更多相关文章
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