Android数据库操作工具类分享

 public class HistoryDAO { private DBConnection dbc = null; private SQLiteDatabase db = null; private Context context; //数据库上下文 public HistoryDAO(Context context) { this.context = context; } //打开数据库 public HistoryDAO open() { dbc = new DBConnection(context); db = dbc.getWritableDatabase(); return this; } //关闭数据库 public void closeAll() { db.close(); dbc.close(); } //  // 增加 //  public void add(Search_HistoryData data, String type) { //    open(); //    ContentValues values = new ContentValues(); //    values.put("content", data.getContent()); //    values.put("type", data.getType()); //    db.insert("history", null, values); //    closeAll(); //  } // 增加 public void add(Search_HistoryData data, String tableName) { open(); ContentValues values = new ContentValues(); values.put("content", data.getContent()); db.insert(tableName, null, values); closeAll(); } // 增加 工具类的最后五个专用 public void addLawTool(Search_HistoryData data, String tableName) { open(); ContentValues values = new ContentValues(); values.put("content", data.getContent()); values.put("_id", data.getId()); db.insert(tableName, null, values); closeAll(); } // 全查询 public List getAll(String TableName) { open(); List ar = new ArrayList(); Cursor c = db.rawQuery("select * from " + TableName, null); while (c.moveToNext()) { Map map = new HashMap(); map.put("_id", c.getInt(c.getColumnIndex("_id"))); map.put("content", c.getString(c.getColumnIndex("content"))); ar.add(map); } closeAll(); return ar; } // 删除 根据id删除 public void delete(String tableName, int uid) { open(); db.delete("history", "uid=" + uid, null); closeAll(); } //清空表中所有数据 public void delete(String tableName) { open(); db.delete(tableName, null, null); closeAll(); } //判断是否存在 public boolean searchResult(String tableName, String key) { open(); Boolean booleans = db.rawQuery("select * from " + tableName + " where content = ?", new String[]{key}).moveToNext(); closeAll(); return booleans; } //根据库查询表字段 public boolean searchResultToType(String content, String type) { open(); Boolean booleans = db.rawQuery("select * from history where content = ? and type = ?", new String[]{content, type}).moveToNext(); closeAll(); return booleans; } }