isValidDNI static method

bool isValidDNI(
  1. String dni
)

Validates DNI with proper letter algorithm (BOE)

Implementation

static bool isValidDNI(String dni) {
  if (dni.length != 9) return false;
  final number = int.tryParse(dni.substring(0, 8));
  if (number == null) return false;
  final letter = dni[8].toUpperCase();
  const letters = 'TRWAGMYFPDXBNJZSQVHLCKE';
  return letter == letters[number % 23];
}