validateLastName method

String? validateLastName (String value)

Implementation

static String? validateLastName(String value) {
  if (value.isEmpty) {
    return 'Lastname must not be left blank.';
  }
  // ignore: unnecessary_raw_strings
  const String pattern = r"(?=.*?[A-Za-z]).+";
  final RegExp regex = RegExp(pattern);
  if (!regex.hasMatch(value)) {
    return "Invalid Lastname";
  }
  return null;
}