怎样获取当前app的缓存目录？

import { common } from '@kit.AbilityKit';


@Entry
@Component
struct Index {
  @State message: string = 'Hello World';
  private context = getContext(this) as common.UIAbilityContext;

  build() {
    Row() {
      Column() {
        Text(this.message)
          .fontSize(50)
          .fontWeight(FontWeight.Bold)
          .onClick(()=>{
            let applicationContext = this.context.getApplicationContext();
            let cacheDir = applicationContext.cacheDir;
            this.message = cacheDir;

          })
      }
      .width('100%')
    }
    .height('100%')
  }
}

import common from '@ohos.app.ability.common';

@Entry
@Component
export struct GetCacheDirectoryView {
  private context = getContext(this) as common.UIAbilityContext;
  @State cachePath: string = '';

  build() {
    Column() {
      Text(this.cachePath)
        .margin({ bottom: 24 })
      Button() {

        Text('获取应用程序缓存目录地址')
      }
      .onClick(() => {

        const applicationContext = this.context.getApplicationContext();
        // 获取应用文件路径
        const cacheDir = applicationContext.cacheDir;
        this.cachePath = cacheDir + '/test.txt';
      })
      .width(300)
      .height(50)
    }
    .justifyContent(FlexAlign.Center)
    .width('100%')
    .height('100%')
  }
}