isNumerical method Null safety
- {String message = "Validator.isNumerical"}
Returns a Validator that accepts a value that is comprised of only numbers, or empty.
accepts
null, "", " ", "0", " 0", "0 ", "0 1"
rejects
"0xFFFFFF"
Implementation
Validator isNumerical({
String message = "Validator.isNumerical",
}) {
var source = r"^([0-9]* *)*$";
return copy().matches(RegExp(source), message: message);
}