readFileBytes method

@override Future<Uint8List> readFileBytes(String fsPath, { int? maxBytes, })

Reads raw file bytes as Uint8List asynchronously. When maxBytes is set, only reads up to that many bytes.

Implementation

@override
Future<Uint8List> readFileBytes(String fsPath, {int? maxBytes}) async {
  if (maxBytes == null) {
    return await File(fsPath).readAsBytes();
  }
  final raf = await File(fsPath).open(mode: FileMode.read);
  try {
    final size = (await raf.length());
    final readSize = min(size, maxBytes);
    final buffer = Uint8List(readSize);
    int offset = 0;
    while (offset < readSize) {
      final bytesRead = await raf.readInto(buffer, offset, readSize);
      if (bytesRead == 0) break;
      offset += bytesRead;
    }
    return offset < readSize ? buffer.sublist(0, offset) : buffer;
  } finally {
    await raf.close();
  }
}