public bool IsValidAndExistLicenseNumberStr(string i_LicenseNumStrToCheck) { bool isExistLicenseNumber = false; Vehicle.IsValidLicenseNumberStr(i_LicenseNumStrToCheck); if (m_VehicleInTheGarage.ContainsKey(i_LicenseNumStrToCheck.GetHashCode()) == true) { isExistLicenseNumber = true; } return(isExistLicenseNumber); }