toDoubleSafe method
Converts this string to a double, removing commas and other formatting first.
Returns null if the string cannot be parsed as a number.
Example:
String text = '11,111.50';
double? value = text.toDoubleSafe(); // 11111.50
Implementation
double? toDoubleSafe() {
final cleaned = numbersWithDecimal;
if (cleaned.isEmpty) return null;
return double.tryParse(cleaned);
}