isValidOTP static method

String? isValidOTP(
  1. String? otp, {
  2. int length = 6,
})

Validates if the input is a valid numeric OTP of specified length

Implementation

static String? isValidOTP(String? otp, {int length = 6}) {
  if (otp == null || otp.isEmpty) {
    return 'Please enter the verification code.';
  }

  if (otp.length != length) {
    return 'Code must be $length digits.';
  }

  final numericRegExp = RegExp(r'^\d+$');
  if (!numericRegExp.hasMatch(otp)) {
    return 'Code must contain only numbers.';
  }

  return null;
}