formatCurrency method
Formats the number as currency.
Example:
1234.formatCurrency(); // '\$1,234.00'
1234.formatCurrency(symbol: '€'); // '€1,234.00'
1234.formatCurrency(decimals: 0); // '\$1,234'
Implementation
String formatCurrency({String symbol = '\$', int decimals = 2}) {
assert(decimals >= 0, 'decimals must be non-negative');
// Integers have no fractional part, so the decimals are always zeros.
final String fraction = decimals > 0 ? '.${'0' * decimals}' : '';
return '$symbol${formatWithSeparator()}$fraction';
}