The FileSystemDirectoryReader interface of the File and Directory Entries API lets you access the FileSystemFileEntry-based objects (generally FileSystemFileEntry or FileSystemDirectoryEntry) representing each entry in a directory.
The FileSystemDirectoryReader interface's readEntries() method retrieves the directory entries within the directory being read and delivers them in an array to a provided callback function.
The
FileSystemDirectoryReaderinterface of the File and Directory Entries API lets you access the FileSystemFileEntry-based objects (generally FileSystemFileEntry or FileSystemDirectoryEntry) representing each entry in a directory.MDN Reference