private EncryptedString Encrypt_StreamReadToEnd(string text)
        {
            EncryptedString encrypted;

            using (var stream = EncryptingStream.Read(text, _key))
                encrypted = stream.ReadToEnd();

            Assert.AreNotEqual(text, encrypted);
            return(encrypted);
        }
        private EncryptedString Encrypt_StreamRead(string text)
        {
            var encrypted = EncryptedString.Empty;

            using (var stream = EncryptingStream.Read(text, _key))
            {
                var newlyEncrypted = stream.Read(5);
                while (newlyEncrypted != null)
                {
                    encrypted     += newlyEncrypted;
                    newlyEncrypted = stream.Read(5);
                }
            }
            Assert.AreNotEqual(text, encrypted);
            return(encrypted);
        }