HarmonyOS 鸿蒙Next web组件下载文件报错

Web({
  src: "www.baidu.com",
  controller: this.controller1
})
  .domStorageAccess(true).onControllerAttached(() => {
  // console.log("testTag - test");
  try {
    this.delegate.onBeforeDownload((webDownloadItem: web_webview.WebDownloadItem) => {
      console.log("will start a download.");
      // 传入一个下载路径，并开始下载。
      // 如果传入一个不存在的路径，则会下载到默认/data/storage/el2/base/cache/web/目录。
      webDownloadItem.start("/data/storage/el2/base/cache/web/" + webDownloadItem.getSuggestedFileName());
      console.log(webDownloadItem.getSuggestedFileName())
    })
    this.delegate.onDownloadUpdated((webDownloadItem: web_webview.WebDownloadItem) => {
      // 下载任务的唯一标识。
      console.log("download update guid1: " + webDownloadItem.getGuid());
      // 下载的进度。
      console.log("download update guid2: " + webDownloadItem.getPercentComplete());
      // 当前的下载速度。 console.log("download update speed: " + webDownloadItem.getCurrentSpeed()) }) this.delegate.onDownloadFailed((webDownloadItem: web_webview.WebDownloadItem) => { console.log("download failed guid1: " + webDownloadItem.getGuid());
      // 下载任务失败的错误码。
      console.log("download failed guid2: " + webDownloadItem.getLastErrorCode());
    })
    this.delegate.onDownloadFinish((webDownloadItem: web_webview.WebDownloadItem) => {
      console.log("download finish guid: " + webDownloadItem.getGuid())
    }
  }
}