HarmonyOS photoAccessHelper如何获取所有相册的信息

async aboutToAppear(): Promise<void> { 
  const context = getContext(this); 
  const phAccessHelper = photoAccessHelper.getPhotoAccessHelper(context); 
  const predicates = new dataSharePredicates.DataSharePredicates(); 
  const fetchOptions: photoAccessHelper.FetchOptions = { 
    fetchColumns: [], 
    predicates 
  } 
  const sysFetchResult = await phAccessHelper.getAlbums(photoAccessHelper.AlbumType.SYSTEM, photoAccessHelper.AlbumSubtype.ANY, fetchOptions); 
  const userFetchResult = await phAccessHelper.getAlbums(photoAccessHelper.AlbumType.USER, photoAccessHelper.AlbumSubtype.ANY, fetchOptions); 
  console.info('fetchResult', sysFetchResult.getCount()) 
  console.info('fetchResult', userFetchResult.getCount()) 
  const sysAlbum = await this.fetchResultIterator(sysFetchResult); 
  const userAlbum = await this.fetchResultIterator(userFetchResult); 
  sysAlbum.forEach(album => { 
  console.info('sysAlbumName', album.albumName); 
}) 
userAlbum.forEach(album => { 
  console.info('userAlbumName', album.albumName); 
}) 
} 
async fetchResultIterator(fetchResult: photoAccessHelper.FetchResult<photoAccessHelper.Album>, albumList: photoAccessHelper.Album[] = []): Promise<photoAccessHelper.Album[]> { 
  if (fetchResult.isAfterLast()) return albumList; 
  const getPhotoObject = !albumList.length ? fetchResult.getFirstObject() : fetchResult.getNextObject(); 
  const album = await getPhotoObject; 
  albumList.push(album); 
  return this.fetchResultIterator(fetchResult, albumList) 
 
}