C# and ColdFusion AES Encryption not matching - algorithm

Question

I have to encrypt url query sting in C# and pass to ColdFusion page. Can someone help me on writing encryption code using AES algorithm in C#.net that is equivalent to below ColdFusion function? Thanks in advance.
<cfset strLink = Encrypt("top secret", "WTq8zYcZfaWVvMncigHqwQ==", "AES","Hex")>
CF Result:
strLink = 91E72250B8A7EDBC4E5AF37F04E6AB5B
I tried below code in C#, but the results are not matching.
byte[] plainText = Encoding.Unicode.GetBytes("top secret");
byte[] key = Convert.FromBase64String("WTq8zYcZfaWVvMncigHqwQ==");
RijndaelManaged algorithm = new RijndaelManaged();
algorithm.Mode = CipherMode.ECB;
algorithm.Padding = PaddingMode.PKCS7;
algorithm.BlockSize = 128;
algorithm.KeySize = 128;
algorithm.Key = key;
string result;
using (ICryptoTransform encryptor = algorithm.CreateEncryptor())
{
using (MemoryStream memoryStream = new MemoryStream())
{
using (CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
{
cryptoStream.Write(plainText, 0, plainText.Length);
cryptoStream.FlushFinalBlock();
result = Convert.ToBase64String(memoryStream.ToArray());
}
}
}
return result;
C# Result:
HEX = 89F9F3C55CD232362FE1E14240C479BE5B56210FF3913E7B6BA4BCD3C87F9AA7
Base64 = ifnzxVzSMjYv4eFCQMR5vltWIQ/zkT57a6S808h/mqc=

Answer 1

(From comments...)
This is a perfect example of how character encoding makes a big difference.
Believe it or not, it is simply due to using the wrong encoding in the C# code. Encoding.Unicode uses UTF-16, whereas CF's Encrypt function always uses UTF-8 (very different). Consequently, the C# code is encrypting a totally different value than CF. Hence the different results, and why the length of the C# string (hex) is longer than the one returned from CF.
Use Encoding.UTF8.GetBytes() instead of Encoding.Unicode.GetBytes() and the results will match:
byte[] plainText = Encoding.UTF8.GetBytes("top secret");