鸿蒙ArkTS Rdb学习

import Rdb from '@ohos.data.rdb';
import CommonConstants from '../common/constants/CommonConstants';

@Entry
@Component
struct Index {
 @State message: string = 'Hello World';
 private context = getContext(this);
 private rdbStore: Rdb.RdbStore;
 private tableName = 'student';
 private columns: Array<string> = ['id', 'name', 'age', 'gender']

 createRdbStore() {
   const STORE_CONFIG = { name: "RdbTest.db"}
   Rdb.getRdbStore(this.context, STORE_CONFIG, 1)
     .then((rdbStore) => {
       this.rdbStore = rdbStore;
       console.log("Get RdbStore successfully.")
     }).catch((err) => {
       console.log("Get RdbStore failed, err: " + `${err.code} + ${err.message}`)
     })
 }

 createTable() {
   let sqlCreate = 'CREATE TABLE IF NOT EXISTS student(id INTEGER PRIMARY KEY AUTOINCREMENT, name string, ' +
   'gender boolean, age INTEGER)';
   this.rdbStore.executeSql(sqlCreate)
     .then(() => {
       console.info('Create table done.')
     }).catch((error) => {
       console.log(`createTable failed ${error.code}   ${error.message}`);
     })
 }

 insert() {
   const valueBucket = {
     "name": "Lisa",
     "age": 18,
     "gender": true
   }
   this.rdbStore.insert(this.tableName, valueBucket)
     .then((rowId) => {
       console.log("Insert is successful, rowId = " + JSON.stringify(rowId));
     }).catch((error) => {
       console.log(`insert failed ${error.code}   ${error.message}`);
     })
 }

 query() {
   let predicates = new Rdb.RdbPredicates(this.tableName)
   this.rdbStore.query(predicates, this.columns)
     .then((resultSet) => {
       console.log("ResultSet column names: " + resultSet.columnNames)
       console.log("ResultSet column count: " + resultSet.columnCount)
       this.dealWithResultSet(resultSet)
     }).catch((error) => {
       console.log(`query failed ${error.code}   ${error.message}`);
     })
 }

 dealWithResultSet(resultSet) {
   let count = resultSet.rowCount;
   if (count === 0 || typeof count === 'string') {
     console.log(`${CommonConstants.TABLE_TAG}` + 'Query no results!');
   } else {
     resultSet.goToFirstRow();
     const result = [];
     for (let i = 0; i < count; i++) {
       let tmp = {'id': 0, 'name': '', 'age': 0, 'gender': true}
       tmp.id = resultSet.getDouble(resultSet.getColumnIndex('id'));
       tmp.name = resultSet.getDouble(resultSet.getColumnIndex('name'));
       tmp.age = resultSet.getString(resultSet.getColumnIndex('age'));
       tmp.gender = resultSet.getDouble(resultSet.getColumnIndex('gender'));
       result[i] = tmp;
       resultSet.goToNextRow();
     }
     console.info(JSON.stringify(result))
   }
 }

 build() {
   Row() {
     Column() {
       Text(this.message)
         .fontSize(50)
         .fontWeight(FontWeight.Bold)
       Button('createRdbStore')
         .onClick(() => {
           this.createRdbStore();
         })
       Button('createTable')
         .onClick(() => {
           this.createTable();
         })
       Button('insert')
         .onClick(() => {
           this.insert();
         })
       Button('query')
         .onClick(() => {
           this.query();
         })
     }
     .width('100%')
   }
   .height('100%')
 }
}