validator method

  1. @override
OrderIDValidationError? validator(
  1. String value
)
override

A function that must return a validation error if the provided value is invalid and null otherwise.

Implementation

@override
OrderIDValidationError? validator(String value) {
  if (value.isEmpty) {
    return null;
  }
  return _orderIDRegExp.hasMatch(value) && value.length < 30 ? null : OrderIDValidationError.invalid;
}