private bool ValidateAppResponse(string jsonData, Encoding encoding)
        {
            //获取签名
            Dictionary <string, object> data = SDKUtil.JsonToDictionary(jsonData);

            string dataString = (string)data["data"];
            string signString = (string)data["sign"];

            byte[]  signByte = Convert.FromBase64String(signString);
            byte[]  dataByte = encoding.GetBytes(dataString);
            IDigest digest   = DigestUtilities.GetDigest("SHA1");

            digest.BlockUpdate(dataByte, 0, dataByte.Length);
            byte[] dataDigest = DigestUtilities.DoFinal(digest);

            string digestString = BitConverter.ToString(dataDigest).Replace("-", "").ToLower();

            if (appVerifyPubKey == null)
            {
                using (FileStream fileStream = new FileStream("d:/certs/acp_test_app_verify_sign.cer", FileMode.Open))//TODO: 这个是测试环境的证书,切换生产需要改生产证书。
                {
                    X509Certificate certificate = new X509CertificateParser().ReadCertificate(fileStream);
                    this.appVerifyPubKey = certificate.GetPublicKey();
                }
            }
            byte[] digestByte = encoding.GetBytes(digestString);

            ISigner verifier = SignerUtilities.GetSigner("SHA1WithRSA");

            verifier.Init(false, this.appVerifyPubKey);

            verifier.BlockUpdate(digestByte, 0, digestByte.Length);
            return(verifier.VerifySignature(signByte));
        }