isValidCardNumber function

bool isValidCardNumber(
  1. String? cardNumber
)

Checks the input string to see whether or not it is a valid card number, possibly with groupings separated by spaces or hyphens.

@param cardNumber a String that may or may not represent a valid card number @return {@code true} if and only if the input value is a valid card number

Implementation

bool isValidCardNumber(String? cardNumber) {
  String? normalizedNumber = removeSpacesAndHyphens(cardNumber);
  return isValidLuhnNumber(normalizedNumber) &&
      isValidCardLength(normalizedNumber);
}