- 鸿蒙多线程收藏存储/离线缓存等

import rdb from '@ohos.data.relationalStore'; import type common from '@ohos.app.ability.common'; import { BusinessError } from '@kit.BasicServicesKit';

const STORE_CONFIG: rdb.StoreConfig = { name: 'shop.db', securityLevel: rdb.SecurityLevel.S2 }; const SQL_CREATE_TABLE = 'CREATE TABLE IF NOT EXISTS goods(id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT NOT NULL)'; const TABLE_NAME = 'goods';

export class GoodsItemType { id: number = 0 name:string = ''

constructor(name: string) { this.name = name; } }

export class GoodsRdb { public table: rdb.RdbStore | undefined = undefined;

public async initRdbStore(context: common.Context): Promise { console.log('init rdbStore begin');

if (this.table) return

try {
  this.table = await rdb.getRdbStore(context, STORE_CONFIG);
  console.log('getRdbStore succeed');
  // 创建数据库表
  await this.table.executeSql(SQL_CREATE_TABLE)
  console.log('create table succeed');
} catch (err) {
  console.log(`getRdbStore failed, err: ${err}`);
  return;
}

}

// 查询数据库 public async query(context:common.Context): Promise<Array> { console.log('query begin');

if (!this.table) await this.initRdbStore(context);

try {
  const predicates = new rdb.RdbPredicates(TABLE_NAME);
  const resultSet: rdb.ResultSet = await this.table!.query(predicates);
  console.log('result is ' + JSON.stringify(resultSet.rowCount));
  // 处理查询到的结果数组
  const temp: Object[] = []
  while (resultSet.goToNextRow()) {
    // const id = resultSet.getLong(resultSet.getColumnIndex('id'));
    // const name = resultSet.getString(resultSet.getColumnIndex('name'));
    // const money = resultSet.getLong(resultSet.getColumnIndex('money'));
    // console.info(`slj id=${id}, name=${name}, money=${money}`);
    temp.push(resultSet.getRow())
  }

  resultSet.close();
  return temp as GoodsItemType[];
} catch (err) {
  console.log('query result error:' + JSON.stringify(err));
  return [];
}

}

// 插入数据库 async insertData(context:common.Context, data: GoodsItemType): Promise { console.log('insert begin');

if (!this.table) await this.initRdbStore(context);

this.table!.insert(TABLE_NAME, {  name: data.name, }, (err: BusinessError, rows: number) => {
  if (err) {
    console.log("Insert failed, err: " + err)
    return
  }
  console.log(`insert done:${rows}`);
})

}

}