Question

我使用SQL lite专家设计了一个数据库，并将其复制到assets文件夹，但我无法将其复制到数据库文件夹。

我不想使用我的代码，因为它不起作用......

任何人都可以共享代码吗？

Answer 1

我的问题解决了：）

从Database到Asset Folder复制Databases Folder有问题的每个人都可以使用以下代码

package com.example.zedaastan;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class database extends SQLiteOpenHelper {

private static SQLiteDatabase mydb;
private static final int DATABASE_VERSION = 1;
private static final String DB_NAME = "database";
private static final String DB_PATH = "/databases/";
static Context ctx;


@Override
public void onCreate(SQLiteDatabase arg0) {
    // TODO Auto-generated method stub

}

public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
    // TODO Auto-generated method stub

}



public database(Context context) {
    super(context, DB_NAME, null, DATABASE_VERSION);
    ctx = context;
}

public void CopyDataBaseFromAsset() throws IOException{

    InputStream myInput = ctx.getAssets().open(DB_NAME);
// Path to the just created empty db
String outFileName = getDatabasePath(); 
// if the path doesn't exist first, create it 
File f = new File(ctx.getApplicationInfo().dataDir + DB_PATH);
    if (!f.exists())
        f.mkdir(); 
// Open the empty db as the output stream
    OutputStream myOutput = new FileOutputStream(outFileName);
// transfer bytes from the inputfile to the outputfile
    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer)) > 0) {
        myOutput.write(buffer, 0, length);
    } 
// Close the streams
    myOutput.flush();
    myOutput.close();
    myInput.close();
}

public void open(){
File dbFile = ctx.getDatabasePath(DB_NAME);
}

public void close(){
    mydb.close();
}

private static String getDatabasePath() {

    return ctx.getApplicationInfo().dataDir + DB_PATH
            + DB_NAME;
}

public SQLiteDatabase openDataBase() throws SQLException{
    File dbFile = ctx.getDatabasePath(DB_NAME);
    if (!dbFile.exists()) {
        try {
            CopyDataBaseFromAsset();
            System.out.println("Copying sucess from Assets folder");
        } catch (IOException e) {
            throw new RuntimeException("Error creating source database", e);
        }
    }

    return SQLiteDatabase.openDatabase(dbFile.getPath(), null,         SQLiteDatabase.NO_LOCALIZED_COLLATORS |
            SQLiteDatabase.CREATE_IF_NECESSARY);
}

如何将数据库从资源文件夹复制到数据库文件夹？

1 个答案: