在Flutter 中将数字转换为印度文字样式

这是一个to-words的精简版本，取自"脚本世界".

String convert(int number) {
  final isNegativeNumber = number < 0;
  if (isNegativeNumber) {
    number = number.abs();
  }

  final words = <String>[];
  final match =
      numberWordsMapping.entries.firstWhere((entry) => number >= entry.key);
  if (number < 100) {
    words.add(match.value);
    number -= match.key;
    if (number > 0) {
      words.add(convert(number));
    }
  } else {
    final quotient = number ~/ match.key;
    final remainder = number % match.key;
    words
      ..add(convert(quotient))
      ..add(match.value);

    if (remainder > 0) {
      words.add(convert(remainder));
    }
  }

  if (isNegativeNumber) words.insert(0, 'Minus');
  return words.join(' ');
}


const numberWordsMapping = {
  100000000000: 'Kharba',
  1000000000: 'Arba',
  10000000: 'Crore',
  100000: 'Lakh',
  1000: 'Thousand',
  100: 'Hundred',
  90: 'Ninety',
  80: 'Eighty',
  70: 'Seventy',
  60: 'Sixty',
  50: 'Fifty',
  40: 'Forty',
  30: 'Thirty',
  20: 'Twenty',
  19: 'Nineteen',
  18: 'Eighteen',
  17: 'Seventeen',
  16: 'Sixteen',
  15: 'Fifteen',
  14: 'Fourteen',
  13: 'Thirteen',
  12: 'Twelve',
  11: 'Eleven',
  10: 'Ten',
  9: 'Nine',
  8: 'Eight',
  7: 'Seven',
  6: 'Six',
  5: 'Five',
  4: 'Four',
  3: 'Three',
  2: 'Two',
  1: 'One',
  0: 'Zero',
};

OUTPUT个

1 = One
10 = Ten
12 = Twelve
30 = Thirty
42 = Forty Two
99 = Ninety Nine
111 = One Hundred Eleven
101 = One Hundred One
100 = One Hundred
999 = Nine Hundred Ninety Nine
1000 = One Thousand
1001 = One Thousand One
9990 = Nine Thousand Nine Hundred Ninety Nine
10000 = Ten Thousand
10042 = Ten Thousand Forty Two
9999999999999 = Ninety Nine Kharba Ninety Nine Arba Ninety Nine Crore Ninety Nine Lakh Ninety Nine Thousand Nine Hundred Ninety Nine