numeric static method
FormFieldValidator that requires the field's value to be a valid number.
Implementation
static FormFieldValidator numeric({
String errorText = "Value must be numeric.",
}) {
return (valueCandidate) {
var valueString = "$valueCandidate";
if (num.tryParse(valueString) == null && valueString.isNotEmpty) {
return errorText;
}
return null;
};
}