fromBase function

List<int> fromBase(
  1. String input,
  2. String alphabet, {
  3. int padding = 61,
})

Converts given base encoded string to data bytes

Implementation

List<int> fromBase(String input, String alphabet, {int padding = 61}) {
  final ret = input.codeUnits
      .map((e) => e == padding ? -2 : alphabet.indexOf(String.fromCharCode(e)))
      .where((e) => e != -2)
      .toList();
  if (ret.contains(-1)) {
    throw Exception('invalid input');
  }
  return fromBaseBytes(ret, alphabet.codeUnits.length);
}