toCurrency method
Num to locale currency with symbol or not
Implementation
String? toCurrency({bool? withSymbol}) {
if (isNullOrZero) {
return null;
} else {
if (withSymbol == false) {
return NumberFormat.simpleCurrency(name: '').format(this).trim();
} else {
return NumberFormat.simpleCurrency().format(this).trim();
}
}
}