numberToWordsString function
Returns Persian word of the given number in String. Number can contain commas.
You can determine returned string has ordinal suffix or not by ordinal
flag.
Implementation
String? numberToWordsString(String number, {bool ordinal = false}) {
if (number.isEmpty) return null;
if (number == '0') return zeroFa;
return _convert(removeCommas(number).toInt(), ordinal);
}