RawJSON_0">【HarmonyOS】如何读取Raw下的JSON文件内容

一、问题背景：

读取工程中/resources下json文件，json文件推荐放在rawfile路径下，通过getRawFileContent接口访问。但是通过该接口拿到的是Uint8Array类型数据，那怎么拿到JSON的文本内容？

二、解决方案：

1.首先通过getRawFileContent拿到文件的字节流内容。

  getContext().resourceManager.getRawFileContent("vibration.json")

2.通过util.TextDecoder设置编码，解析字节流内容转化为string文本。

import { util, buffer } from '@kit.ArkTS';let decoder = util.TextDecoder.create('utf-8');let json = decoder.decodeToString(rawFile);

三、源码示例：

JSONTestPage.ets

import { BusinessError } from '@kit.BasicServicesKit';
import { util, buffer } from '@kit.ArkTS';@Entry
@Component
struct JSONTestPage {private TAG: string = "JSONTestPage";@State showText: string = "";aboutToAppear(): void {this.getRawJson();}/*** 获取JSON*/private getRawJson(){try {getContext().resourceManager.getRawFileContent("vibration.json").then((value: Uint8Array) => {let rawFile = value;let decoder = util.TextDecoder.create('utf-8');let json = decoder.decodeToString(rawFile);console.info(this.TAG, "json: " + json);this.showText = json;}).catch((error: BusinessError) => {console.error("getRawFileContent promise error is " + error);});} catch (error) {let code = (error as BusinessError).code;let message = (error as BusinessError).message;console.error(`promise getRawFileContent failed, error code: ${code}, message: ${message}.`);}}build() {Scroll(){Row() {Text(this.showText).fontSize(50).fontWeight(FontWeight.Bold)}}.height('100%').width('100%')}
}

vibration.json

{"MetaData": {"Create": "2023-01-09","Description": "a haptic case","Version": 1.0,"ChannelNumber": 1},"Channels": [{"Parameters": {"Index": 0},"Pattern": [{"Event": {"Type": "transient","StartTime": 0,"Parameters": {"Frequency": 31,"Intensity": 100}}},{"Event": {"Type": "continuous","StartTime": 40,"Duration": 54,"Parameters": {"Frequency": 30,"Intensity": 38,"Curve": [{"Time": 0,"Frequency": 0,"Intensity": 0},{"Time": 1,"Frequency": 15,"Intensity": 0.5},{"Time": 40,"Frequency": -8,"Intensity": 1.0},{"Time": 54,"Frequency": 0,"Intensity": 0}]}}}]}]
}