加密和解密函数

/**//// <summary>
    /// SecureAttribute 的摘要说明。
    /// </summary>
    public class SecureAttribute
    {
        private static byte[] keys = new byte[]
        {
            133, 98, 72, 143, 17, 162, 187, 83, 7, 15, 179, 199, 247
        };
        private static byte[] vectors = new byte[]
        {
            9, 139, 23, 177, 213, 63, 90, 129, 53, 122, 187, 190, 32, 10, 135, 138, 92
        };
private static byte[] keys = new byte[]
        {
            133, 98, 72, 143, 17, 162, 187, 83, 7, 15, 179, 199, 247
        };
        private static byte[] vectors = new byte[]
        {
            9, 139, 23, 177, 213, 63, 90, 129, 53, 122, 187, 190, 32, 10, 135, 138, 92
        };

        // 加密串
        public static string EncryptString(string Source)
        {
            ASCIIEncoding textConverter = new ASCIIEncoding();
            RC2CryptoServiceProvider rc2CSP = new RC2CryptoServiceProvider();
            byte[] encrypted;
            byte[] toEncrypt;
            rc2CSP.EffectiveKeySize = 128;
            // 生成加密器.
            ICryptoTransform encryptor = rc2CSP.CreateEncryptor(keys, vectors);
            
            // 加密数据
            MemoryStream msEncrypt = new MemoryStream();
            CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write);

            // 转换数据到字节表
            toEncrypt = textConverter.GetBytes(Source);

            // 执行加密
            csEncrypt.Write(toEncrypt, 0, toEncrypt.Length);
            csEncrypt.FlushFinalBlock();

            // 取加密过的字节流
            encrypted = msEncrypt.ToArray();

            // 返回结果
            return Convert.ToBase64String(encrypted);
        }

        // 解密串
        public static string DecryptString(string Source)
        {
            byte[] fromEncrypt;
            byte[] encrypted;

            ASCIIEncoding textConverter = new ASCIIEncoding();
            RC2CryptoServiceProvider rc2CSP = new RC2CryptoServiceProvider();
            rc2CSP.EffectiveKeySize = 128;

            // 生成解密器
            ICryptoTransform decryptor = rc2CSP.CreateDecryptor(keys, vectors);

            // 取得源加密字节流
            encrypted    = System.Convert.FromBase64String(Source);

            // 解密字节流
            MemoryStream msDecrypt = new MemoryStream(encrypted);
            CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read);

            fromEncrypt = new byte[encrypted.Length];
            csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length);
            int n = 0;
            foreach (byte b in fromEncrypt)
            {
                if (b != 0)
                {
                    n++;
                }
                else
                {
                    break;
                }
            }
            byte[] bs = new byte[n];
            for (int i = 0; i < n; i++)
            {
                bs[i] = fromEncrypt[i];
            }
            string s = textConverter.GetString(bs);

            // 返回解密串
            return s;
        }
    }