如何从android中的sqlitedatabase文件导入数据 [英] how to import data from sqlitedatabase file in android
本文介绍了如何从android中的sqlitedatabase文件导入数据的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
大家好,
我需要从资源文件夹中提供的sqlitedatabase文件中导入数据。
提前感谢
Hi all,
i need to import data form sqlitedatabase file which is aviable in assets folders.
thanks in advance
推荐答案
public static String DB_FILEPATH = "/data/data/{package_name}/databases/database.db";
/**
* Copies the database file at the specified location over the current
* internal application database.
* */
public boolean importDatabase(String dbPath) throws IOException {
// Close the SQLiteOpenHelper so it will commit the created empty
// database to internal storage.
close();
File newDb = new File(dbPath);
File oldDb = new File(DB_FILEPATH);
if (newDb.exists()) {
FileUtils.copyFile(new FileInputStream(newDb), new FileOutputStream(oldDb));
// Access the copied database so SQLiteHelper will cache it and mark
// it as created.
getWritableDatabase().close();
return true;
}
return false;
}
FileUtils
FileUtils
public class FileUtils {
/**
* Creates the specified <code>toFile</code> as a byte for byte copy of the
* <code>fromFile</code>. If <code>toFile</code> already exists, then it
* will be replaced with a copy of <code>fromFile</code>. The name and path
* of <code>toFile</code> will be that of <code>toFile</code>.<br/>
* <br/>
* <i> Note: <code>fromFile</code> and <code>toFile</code> will be closed by
* this function.</i>
*
* @param fromFile
* - FileInputStream for the file to copy from.
* @param toFile
* - FileInputStream for the file to copy to.
*/
public static void copyFile(FileInputStream fromFile, FileOutputStream toFile) throws IOException {
FileChannel fromChannel = null;
FileChannel toChannel = null;
try {
fromChannel = fromFile.getChannel();
toChannel = toFile.getChannel();
fromChannel.transferTo(0, fromChannel.size(), toChannel);
} finally {
try {
if (fromChannel != null) {
fromChannel.close();
}
} finally {
if (toChannel != null) {
toChannel.close();
}
}
}
}
}
-KR
-KR
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