public void TestECDSAImportExport()
        {
            var key       = ECDsaHelper.CreateECDsaCng256();
            var expPubKey = key.ExportPublicKeyRaw();

            var impPubKey = ECDsaHelper.ImportPublicKey(expPubKey);

            Assert.NotNull(impPubKey);

            var expPriKey = key.ExportPrivateKeyRaw();
            var impPriKey = ECDsaHelper.ImportPrivateKey(expPubKey, expPriKey);

            Assert.NotNull(impPriKey);
        }