HarmonyOS 如何读取本地json文件

参考demo：

import { Context } from '@ohos.abilityAccessCtrl';
import buffer from '@ohos.buffer';

@Entry
@Component
struct Index {
  private context: Context = getContext(this);
  private str: string=''

  getRawFile(): ESObject {
    //调用getRawFileContent接口获取json文件内容，并读为string
    getContext(this).resourceManager.getRawFileContent("a.json", (err, data) => {
      try {
        this.str = buffer.from(data.buffer).toString();

      } catch (e) {
        console.info(JSON.stringify(e))
      }
    })

    try {
      let data: Uint8Array = this.context.resourceManager.getRawFileContentSync("a.json");
      this.str = buffer.from(data.buffer).toString();
      console.log(this.str)
    } catch (e) {
      console.info(JSON.stringify(e))
    }

    let obj: ESObject = JSON.parse(this.str)
    return obj
  }

  build() {
    Column() {
      Button("get")
        .onClick(() => {
          this.getRawFile()
        })
    }.width('100%')
  }
}