oneSpecial static method

ValidationRule oneSpecial({
  1. String message = 'Must contain at least one special character',
})

Validation rule to require at least one special character.

Special characters include: !@#$%^&*(),.?":{}|<>. Returns message if none are found.

Implementation

static ValidationRule oneSpecial({
  String message = 'Must contain at least one special character',
}) {
  return ValidationRule(
    (value) =>
        RegExp(r'[!@#$%^&*(),.?":{}|<>]').hasMatch(value ?? '') ? null : '',
    message,
  );
}