C# DES 加密问题！请高手帮帮忙！急急急.......

Question

byte[] Key = { 0xF0, 0x3F, 0xB3, 0xF0, 0x8A, 0x0F, 0xA7, 0x9B };
byte[] IV  = {0x24 ,0xF9 ,0x04 ,0xCC ,0xDB ,0xF0 ,0xCC ,0x81} ;
CipherMode Mode=CipherMode.ECB;
PaddingMode Padding= PaddingMode.PKCS7;
byte[] cipherbytes;
加密如下：
SymmetricAlgorithm sa =CreateSymmetricAlgorithm();
sa.Key = Key;
sa.IV = IV;
sa.Mode = Mode;
sa.Padding = Padding;
MemoryStream ms = new MemoryStream();
CryptoStream cs = new CryptoStream(ms, sa.CreateEncryptor(),CryptoStreamMode.Write);
byte[] plainbytes =Encoding.UTF8.GetBytes(textPlaintext.Text);
cs.Write(plainbytes, 0, plainbytes.Length);
cs.Close();
cipherbytes = ms.ToArray();
ms.Close();
textCiphertext.Text = Encoding.UTF8.GetString(cipherbytes);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < cipherbytes.Length; i++)
{sb.Append(String.Format("{0:X2} ", cipherbytes[i])); }
textCipherbytes.Text = sb.ToString();
解密如下：
SymmetricAlgorithm sa =CreateSymmetricAlgorithm();
sa.Key = Key;
sa.Mode = Mode;
sa.Padding = Padding;
sa.IV = IV;
MemoryStream ms = new MemoryStream(cipherbytes);
CryptoStream cs = new CryptoStream(ms,sa.CreateDecryptor(),CryptoStreamMode.Read);
byte[] plainbytes =new Byte[cipherbytes.Length];
cs.Read(plainbytes, 0, cipherbytes.Length);
cs.Close();
ms.Close();
textRecoveredPlaintext.Text =Encoding.UTF8.GetString(plainbytes);

Answer 1

      忘了个函数
 SymmetricAlgorithm CreateSymmetricAlgorithm()
        {            return DES.Create();        }