【Harmony OS】【ARK UI】ets实现文件读写操作
1.准备阶段
关于该功能的实现我们需要学习以下的资料:
1.1【ARKUI】ets怎么实现文件操作
1.2 文件管理
1.3 Ability上下文
2.demo实现
2.1 文件路径读取
参考context.getFilesDir来进行获取文件路径,代码如下
private getCacheDir(){ var context = ability_featureAbility.getContext(); context.getFilesDir() .then((data) => { console.log('File directory obtained. Data:' + data); this.path=data; }).catch((error) => { console.error('Failed to obtain the file directory. Cause: ' + error.message); }) }
2.2文件写入操作
参考fileio.createStream和write和flush相关Api,资料和代码如下
实现代码
private writeFile(){ let ss= fileio.createStreamSync(this.path+"/111.txt", "w+"); let num = ss.write("你好 2022",null); ss.flush(); console.log("写入成功") }
2.3文件读取文件操作
想实现文件的读取,需要参考read的Api,资料和代码如下:
代码如下:
private readFile(){ let ss = fileio.createStreamSync(this.path+"/111.txt", "r+"); ss.read(new ArrayBuffer(4096),null,function (err, readOut) { if (!err) { let encodedString = String.fromCodePoint.apply(null, new Uint8Array(readOut.buffer)); let decodedString = decodeURIComponent(escape(encodedString));//没有这一步中文会乱码 console.log("读取文件内容:"+decodedString); } }); }
3.运行效果
3.1全部代码如下
import fileio from '@ohos.fileio';import ability_featureAbility from '@ohos.ability.featureAbility';@Entry@Componentstruct MyFileStream { @State path:string=""; private getFilesDirNew(){ var context = ability_featureAbility.getContext(); context.getFilesDir() .then((data) => { console.log('获取文件路径成功' + data); this.path=data; }).catch((error) => { console.error('Failed to obtain the file directory. Cause: ' + error.message); }) } private writeFile(){ let ss= fileio.createStreamSync(this.path+"/111.txt", "w+"); let num = ss.write("你好 2022",null); ss.flush(); console.log("写入成功") } private readFile(){ let ss = fileio.createStreamSync(this.path+"/111.txt", "r+"); ss.read(new ArrayBuffer(4096),null,function (err, readOut) { if (!err) { let encodedString = String.fromCodePoint.apply(null, new Uint8Array(readOut.buffer)); let decodedString = decodeURIComponent(escape(encodedString));//没有这一步中文会乱码 console.log("读取文件内容:"+decodedString); } }); } build() { Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) { Text('获取文件路径') .fontSize(50) .fontWeight(FontWeight.Bold) .backgroundColor(Color.Red) .onClick(this.getFilesDirNew.bind(this)) Text('写入文字') .fontSize(50) .fontWeight(FontWeight.Bold) .backgroundColor(Color.White) .onClick(this.writeFile.bind(this)) Text('读取文字') .fontSize(50) .fontWeight(FontWeight.Bold) .backgroundColor(Color.Red) .onClick(this.readFile.bind(this)) } .width('100%') .height('100%') }}
3.2运行效果如下
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