HarmonyOS之sqlite数据库的使用-编程知识

从API Version 9开始，鸿蒙开发中sqlite使用新接口@ohos.data.relationalStore

但是 relationalStore在 getRdbStore操作时，在预览模式运行或者远程模拟器运行都会报错，导致无法使用。查了一圈说只有在真机上可以正常使用，因此这里暂且使用 @ohos.data.rdb

二者的接口非常相似，会使用了ohos.data.rdb，自然也会使用ohos.data.relationalStore

在harmonyos开发中，操作数据库时，我们通常习惯将一个功能模块数据库操作全部写在一个ets文件中并export，在界面文件中直接导入使用。

1.数据库配置以及建表

新建userDb.ets文件并添加以下代码

import data_rdb from '@ohos.data.rdb'
const STORE_CONFIG = {name: "test.db"}
const TAB_USER = "user"
const CREATE_TABLE_CODE = "CREATE TABLE IF NOT EXISTS "+TAB_USER+" ("+ "id INTEGER PRIMARY KEY AUTOINCREMENT, "+ "name TEXT , "+ "age TEXT , "+ "sex TEXT ) "
export function createTable(context) {data_rdb.getRdbStore(context,STORE_CONFIG, 1, function (err, rdbStore) {rdbStore.executeSql(CREATE_TABLE_CODE)console.info('create table done.')})
}

在User.ets界面导入并调用

import {createTable} from '../utils/userDb'aboutToAppear() {createTable(getContext(this))
}

2.插入数据

userDb.ets文件添加 insertData方法，这里需要注意的是promise的用法，因为需要将执行结果返回界面，所以方法里面多次使用了Promise来返回结果

插入的字段要和数据库字段保持一致。

export function insertData(context,list):any{const promise = data_rdb.getRdbStore(context,STORE_CONFIG, 1)return promise.then(async (rdbStore) => {let arr:any = [];for(let i:number=0; i<list.length; i++){const obj = list[i]const item ={name: obj.name,age: obj.age,sex: obj.sex}rdbStore.insert(TAB_USER, item);}console.log('--start')console.log('完了')return true;})
}

在User.ets界面导入并调用

import {insertData} from '../utils/userDb'addData(){let array = [];for(let i=0; i<20; i++){array.push({name:'张飞'+i,age: 20+i,sex: '男'})}insertData(getContext(this), array).then(res=>{if(res){this.loading = falsethis.showDialog('添加成功')this.search(true)}})}

3.查询

userDb.ets文件添加 queryDataPage方法，这里用了分页查询的方式，还有一种谓词的查询方式请参考官方文档。

export function queryDataPage(context,param):any {let promise = data_rdb.getRdbStore(context, STORE_CONFIG, 1)return promise.then(async (rdbStore) => {const sql: string = "select * from "+TAB_USER+" where name like ? " +"order by id  asc limit  ? OFFSET ? ";console.log('----sql---', sql)const pS = param.pageSizeconst page = param.pageconsole.log('param.code', param.code)console.log('pS', pS)console.log('(page-1)*pS', (page - 1) * pS)// param.code,pS,(page-1)*pS]let promisequery = rdbStore.querySql(sql, [param.code, pS, (page - 1) * pS])return promisequery.then(async (resultSet) => {const rowCount = resultSet.rowCount;let list = [];console.log("rowCount --" + rowCount)resultSet.goToFirstRow();for (let i = 0; i < rowCount; i++) {const name = resultSet.getString(resultSet.getColumnIndex("NAME"))const age = resultSet.getString(resultSet.getColumnIndex("AGE"))const sex = resultSet.getString(resultSet.getColumnIndex("SEX"))const id = resultSet.getString(resultSet.getColumnIndex("ID"))resultSet.goToNextRow();const data = {name,id,age,sex,}list.push(data);}resultSet.close();console.log('--array--', list.length)return list;})}).catch((err) => {console.log("Get RdbStore failed, err: " + err)})
}

在User.ets界面导入并调用

import {queryDataPage} from '../utils/userDb'@State list:Array<any> = []@State keyword:string = ""@State page:number = 1@State pageSize:number = 20
search(firstPage:boolean){if(firstPage){this.page = 1}const params = {code: '%'+this.keyword+'%',page: this.page,pageSize: this.pageSize,}queryDataPage(getContext(this), params).then(data=>{if(data){console.log('res',JSON.stringify(data));if(this.page == 1){this.list = data} else {this.list = this.list.concat(data);}}})}

4.更新数据

userDb.ets文件添加 updateData方法

export  function updateData(context,newInfo):any{const promise = data_rdb.getRdbStore(context,STORE_CONFIG, 1)return promise.then(async (rdbStore) => {let predicates = new data_rdb.RdbPredicates(TAB_USER);predicates.equalTo("id", newInfo.id)let promiseUp = rdbStore.update(newInfo, predicates)return promiseUp.then(async (rows) => {if(rows == 1){return true}}).catch((err) => {console.info("Updated failed, err: " + err)return false})})
}

在User.ets界面导入并调用

import {updateData} from '../utils/userDb'updateOne(item:any){item.name = '张飞111'updateData(getContext(this), item).then(res=>{if(res){this.showDialog('更新成功')this.search(true)}})}

5.删除数据

userDb.ets文件添加 deleteOneData方法

export function deteteOneData(context,id):any{const promise = data_rdb.getRdbStore(context,STORE_CONFIG, 1)return promise.then(async (rdbStore) => {let predicates = new data_rdb.RdbPredicates(TAB_USER);predicates.equalTo("id", id)const result = rdbStore.delete(predicates);console.log('--result--'+JSON.stringify(result))return true;})
}

在User.ets界面导入并调用

import {deteteOneData} from '../utils/userDb'deleteOne(id:string){deteteOneData(getContext(this), id).then(res=>{if(res){this.showDialog('删除成功')this.search(true)}})}

6.界面效果

点击右上角Add按钮，插入数据；

点击删除按钮，删除一条数据；

点击编辑按钮，将该条数据姓名字段更新为马超000。

7.完整代码

界面文件 User.ets

import {createTable,insertData,deteteOneData,updateData,queryDataPage} from '../utils/userDb'
@Entry
@Component
struct User {controller: SearchController = new SearchController()@State codeList:Array<any> = [];@State list:Array<any> = [];@State loading:boolean = false;@State keyword:string = "";@State page:number = 1;@State pageSize:number = 20;aboutToAppear() {createTable(getContext(this))}onReachEnd(){console.log('--------onReachEnd---');//this.page = this.page+1this.search(false)}search(firstPage:boolean){if(firstPage){this.page = 1}const params = {code: '%'+this.keyword+'%',page: this.page,pageSize: this.pageSize,}queryDataPage(getContext(this), params).then(data=>{if(data){console.log('res',JSON.stringify(data));if(this.page == 1){this.list = data} else {this.list = this.list.concat(data);}}})}addData(){let array = [];for(let i=0; i<20; i++){array.push({name:'张飞'+i,age: 20+i,sex: '男'})}insertData(getContext(this), array).then(res=>{if(res){this.loading = falsethis.showDialog('添加成功')this.search(true)}})}deleteOne(id:string){deteteOneData(getContext(this), id).then(res=>{if(res){this.showDialog('删除成功')this.search(true)}})}updateOne(item:any){item.name = '马超000'updateData(getContext(this), item).then(res=>{if(res){this.showDialog('更新成功')this.search(true)}})}showDialog(text:string){AlertDialog.show({title: '提示',message: text,autoCancel: true,alignment: DialogAlignment.Center,gridCount: 4,offset: { dx: 0, dy: -20 },primaryButton: {value: '确定',action: () => {console.info('Callback when the first button is clicked')}},})}toAddData(){AlertDialog.show({title: '提示',message: '确定要添加数据吗',autoCancel: true,alignment: DialogAlignment.Center,offset: { dx: 0, dy: -20 },gridCount: 5,primaryButton: {value: '确定',action: () => {console.info('确定 is clicked')this.loading = truethis.addData()}},secondaryButton: {value: '取消',action: () => {console.info('取消 is clicked')}},cancel: () => {console.info('Closed callbacks')}})}@Builder NavigationMenus() {Row() {Text("Add").width(32).height(28).onClick(()=>this.toAddData())}}@Builder buildList(){Row(){Text('姓名')Text('年龄')Text('性别')Text('操作')}.justifyContent(FlexAlign.SpaceAround).width('100%').padding({top:5,bottom: 10})List({ space: 20, initialIndex: 0 }) {ForEach(this.list, (item) => {ListItem() {Row(){Text(item.name)Text(item.age)Text(item.sex)Row(){Text('删除').onClick(()=>{this.deleteOne(item.id)}).fontColor(Color.Red).margin({right:5})Text('编辑').onClick(()=>{this.updateOne(item)}).fontColor(Color.Blue)}}.justifyContent(FlexAlign.SpaceAround).width('100%')}.editable(true)}, item => item.name)}.onScrollIndex((firstIndex: number, lastIndex: number) => {//console.info('first' + firstIndex)//console.info('last' + lastIndex)}).onReachEnd(()=>{this.onReachEnd()}).listDirection(Axis.Vertical) // 排列方向.divider({ strokeWidth: 2, color: 0xFFFFFF, startMargin: 20, endMargin: 20 }) // 每行之间的分界线.edgeEffect(EdgeEffect.None) // 滑动到边缘无效果.chainAnimation(false) // 联动特效关闭.width('100%')}@Builder buildSearch(){Search({ value: this.keyword, placeholder: '请输入姓名...', controller: this.controller }).searchButton('搜索').width('100%').height(40).backgroundColor('#F5F5F5').placeholderColor(Color.Grey).placeholderFont({ size: 14, weight: 400 }).textFont({ size: 14, weight: 400 }).onSubmit((value: string) => {console.log('---999')//this.submitValue = valuethis.keyword = valuethis.search(true)}).onChange((value: string) => {this.keyword = value})}build() {Column(){Navigation() {Column(){this.buildSearch()if(this.loading){Column(){LoadingProgress().color(Color.Blue)}.width('40%').height('40%')}this.buildList()}.height('100%')}.title("用户管理").menus(this.NavigationMenus).titleMode(NavigationTitleMode.Mini)}.height('100%')}
}

数据操作文件 userDb.ets

import data_rdb from '@ohos.data.rdb'
const STORE_CONFIG = {name: "test.db"}
const TAB_USER = "user"
const CREATE_TABLE_CODE = "CREATE TABLE IF NOT EXISTS "+TAB_USER+" ("+ "id INTEGER PRIMARY KEY AUTOINCREMENT, "+ "name TEXT , "+ "age TEXT , "+ "sex TEXT ) "
export function createTable(context) {data_rdb.getRdbStore(context,STORE_CONFIG, 1, function (err, rdbStore) {rdbStore.executeSql(CREATE_TABLE_CODE)console.info('create table done.')})
}
export  function updateData(context,newInfo):any{const promise = data_rdb.getRdbStore(context,STORE_CONFIG, 1)return promise.then(async (rdbStore) => {let predicates = new data_rdb.RdbPredicates(TAB_USER);predicates.equalTo("id", newInfo.id)let promiseUp = rdbStore.update(newInfo, predicates)return promiseUp.then(async (rows) => {if(rows == 1){return true}}).catch((err) => {console.info("Updated failed, err: " + err)return false})})
}
export function insertData(context,list):any{const promise = data_rdb.getRdbStore(context,STORE_CONFIG, 1)return promise.then(async (rdbStore) => {let arr:any = [];for(let i:number=0; i<list.length; i++){const obj = list[i]const item ={name: obj.name,age: obj.age,sex: obj.sex}rdbStore.insert(TAB_USER, item);}console.log('--start')console.log('完了')return true;})
}
export function deteteOneData(context,id):any{const promise = data_rdb.getRdbStore(context,STORE_CONFIG, 1)return promise.then(async (rdbStore) => {let predicates = new data_rdb.RdbPredicates(TAB_USER);predicates.equalTo("id", id)const result = rdbStore.delete(predicates);console.log('--result--'+JSON.stringify(result))return true;})
}
export function detelteAllCode(context){data_rdb.getRdbStore(context,STORE_CONFIG, 1, function (err, rdbStore) {rdbStore.executeSql("delete from "+TAB_USER)console.info('--delete code done.')})}
export function queryDataPage(context,param):any {let promise = data_rdb.getRdbStore(context, STORE_CONFIG, 1)return promise.then(async (rdbStore) => {const sql: string = "select * from "+TAB_USER+" where name like ? " +"order by id  asc limit  ? OFFSET ? ";console.log('----sql---', sql)const pS = param.pageSizeconst page = param.pageconsole.log('param.code', param.code)console.log('pS', pS)console.log('(page-1)*pS', (page - 1) * pS)// param.code,pS,(page-1)*pS]let promisequery = rdbStore.querySql(sql, [param.code, pS, (page - 1) * pS])return promisequery.then(async (resultSet) => {const rowCount = resultSet.rowCount;let list = [];console.log("rowCount --" + rowCount)resultSet.goToFirstRow();for (let i = 0; i < rowCount; i++) {const name = resultSet.getString(resultSet.getColumnIndex("NAME"))const age = resultSet.getString(resultSet.getColumnIndex("AGE"))const sex = resultSet.getString(resultSet.getColumnIndex("SEX"))const id = resultSet.getString(resultSet.getColumnIndex("ID"))resultSet.goToNextRow();const data = {name,id,age,sex,}list.push(data);}resultSet.close();console.log('--array--', list.length)return list;})}).catch((err) => {console.log("Get RdbStore failed, err: " + err)})
}