SQLite協助類

標籤：

1、首先寫一個類繼承自SQLiteOpenHelper

public class DBHelper extends SQLiteOpenHelper{    private static final int DATABASE_VERSION = 1;  //資料庫版本號碼    private static final String DATABASE_NAME = "";  //資料庫名稱    public DBHelper(Context context)    {        super(context, DATABASE_NAME, null, DATABASE_VERSION);    }    @Override    public void onCreate(SQLiteDatabase db)    {        String sql = "";        db.execSQL(sql);    }    @Override    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)    {    }}

2、需要一個資料庫管理類，比如插入、刪除等

public abstract class DBDao{    private Context context;    private DBHelper dbhelper;    public SQLiteDatabase sqlitedatabase;    public DBDao(Context context)    {        super();        this.context = context;    }    /**     * 開啟資料庫連接     */    public void openDB(Context context)    {        dbhelper = new DBHelper(context);        sqlitedatabase = dbhelper.getWritableDatabase();    }    /**     * 關閉資料庫連接     */    public void closeDB(Context context)    {        if (sqlitedatabase.isOpen())        {            sqlitedatabase.close();        }    }    /**     * 更新資料     */    public int updata(String table_name, ContentValues values, int id)    {        openDB(context);        int update = sqlitedatabase.update(table_name, values, "_id=?", new String[]{String.valueOf(id)});        closeDB(context);        return update;    }    /**     * 插入資料     */    public void insert(String table_name, ContentValues values)    {        openDB(context);        sqlitedatabase.insert(table_name, null, values);        closeDB(context);    }    /**     * 根據唯一標示_id刪除資料     */    public void delete(String table_name, int id)    {        openDB(context);        try        {            sqlitedatabase.delete(table_name, "_id=?", new String[]{String.valueOf(id)});        }        catch (Exception e)        {            e.printStackTrace();        }        finally        {            closeDB(context);        }    }    /**     * 查詢資料     */    public void search(String table_name, int id)    {        SQLiteDatabase database = dbhelper.getReadableDatabase();        String sql = "select * from " + table_name + " where _id = ?";        Cursor cursor = database.rawQuery(sql, new String[]{String.valueOf(id)});    }}

SQLite協助類