private static string VerbalError(RucaptchaError status)
        {
            switch (status)
            {
            case RucaptchaError.WRONG_USER_KEY:
                return("Rucaptcha secret key has invalid format");

            case RucaptchaError.KEY_DOES_NOT_EXIST:
                return("Wrong Rucaptcha secret key");

            case RucaptchaError.ZERO_BALANCE:
                return("Zero Rucaptcha balance");

            case RucaptchaError.ZERO_CAPTCHA_FILESIZE:
                return("Image file has zero size");

            case RucaptchaError.TOO_BIG_CAPTCHA_FILESIZE:
                return("Image file size too big");

            case RucaptchaError.WRONG_FILE_EXTENSION:
                return("Wrong file extension");

            case RucaptchaError.IMAGE_TYPE_NOT_SUPPORTED:
                return("Image type not supported");

            case RucaptchaError.IP_NOT_ALLOWED:
                return("IP not allowed");

            case RucaptchaError.WRONG_ID_FORMAT:
                return("Wrong captcha ID");

            case RucaptchaError.CAPTCHA_UNSOLVABLE:
                return("Captcha unsolvable");

            default:
                return(string.Empty);
            }
        }
 public RucaptchaErrorException(RucaptchaError Error)
     : base(VerbalError(Error))
 {
     this.Error = Error;
 }