isAlphaNumericWithADot static method

bool isAlphaNumericWithADot(String inputStr)

check if the inputStr is alpha-numeric with a single dot occurence

Implementation

static bool isAlphaNumericWithADot(String inputStr) {
  bool isAlNumSeq = true;
  int index = 0;
  int dotCount = 0;

  if (inputStr.trim().isEmpty) {
    isAlNumSeq = false;
    return isAlNumSeq;
  }

  if (isAlpha(inputStr[0])) {
    while ((index <= inputStr.length - 1) && (isAlNumSeq)) {
      isAlNumSeq = isAlNumSeq &&
          (isDigit(inputStr[index]) ||
              isAlpha(inputStr[index]) ||
              (inputStr[index] == '.'));
      if (inputStr[index] == '.') {
        dotCount++;
      }

      if (!isAlNumSeq) {
        break;
      }

      index++;
    }
  }

  isAlNumSeq = isAlNumSeq && (dotCount == 1);

  return isAlNumSeq;
}