Android sd卡讀取數(shù)據(jù)庫實(shí)例代碼
前言:
本文主要給大家講解如何利用Android SD卡讀取數(shù)據(jù)庫,提供一些代碼如下。先在 Manifest 里添加權(quán)限:
<span style="font-size:16px;"><uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /></span>
然后在 mainActivity 添加方法
<span style="font-size:16px;">SQLiteDatabase db; private final String DATABASE_PATH = android.os.Environment .getExternalStorageDirectory().getAbsolutePath() + "/vote"; private String DATABASE_FILENAME = "db_vote.db"; // 初始化數(shù)據(jù)庫 private SQLiteDatabase openDatabase() { try { String databaseFilename = DATABASE_PATH + "/" + DATABASE_FILENAME; File dir = new File(DATABASE_PATH); if (!dir.exists()) dir.mkdir(); 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; }</span> 感謝閱讀,希望能幫助到大家,謝謝大家,對(duì)本站的支持!
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