/**     * 解密DES     * @param key 密钥，长度必须是8的倍数     * @param data 数据源     * @return 解密内容     */    public final static String decoderDES(String key,String data) throws Exception{        // DES算法要求有一个可信任的随机数源        SecureRandom sr = new SecureRandom();        // 从原始密匙数据创建一个DESKeySpec对象        DESKeySpec dks = new DESKeySpec(key.getBytes("utf-8"));        // 创建一个密匙工厂，然后用它把DESKeySpec对象转换成一个SecretKey对象        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");        SecretKey securekey = keyFactory.generateSecret(dks);        // Cipher对象实际完成解密操作        Cipher cipher = Cipher.getInstance("DES");        // 用密匙初始化Cipher对象        cipher.init(Cipher.DECRYPT_MODE, securekey, sr);        // 正式执行解密操作        return new String(cipher.doFinal(hexStr2ByteArr(data)));    }    /**     * 加密DES     * @param key 加密key     * @param data 加密内容     * @return 加密串     */    public final static String encodeDES(String key,String data) throws Exception{        // DES算法要求有一个可信任的随机数源        SecureRandom sr = new SecureRandom();        // 从原始密匙数据创建DESKeySpec对象        DESKeySpec dks = new DESKeySpec(key.getBytes("utf-8"));        // 创建一个密匙工厂，然后用它把DESKeySpec转换成一个SecretKey对象        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");        SecretKey securekey = keyFactory.generateSecret(dks);        // Cipher对象实际完成加密操作        Cipher cipher = Cipher.getInstance("DES");        // 用密匙初始化Cipher对象        cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);        // 执行加密操作        byte[] buf = cipher.doFinal(data.getBytes("utf-8"));        return byteArr2HexStr(buf);    }

 public static string DES(string str)        {            DESCryptoServiceProvider des = new DESCryptoServiceProvider();            byte[] inputByteArray = Encoding.GetEncoding("UTF-8").GetBytes(str);            //建立加密对象的密钥和偏移量                //原文使用ASCIIEncoding.ASCII方法的GetBytes方法                //使得输入密码必须输入英文文本              des.Mode = CipherMode.ECB;            des.Key = ASCIIEncoding.UTF8.GetBytes(key);            des.IV = ASCIIEncoding.UTF8.GetBytes(key);            MemoryStream ms = new MemoryStream();            CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);            cs.Write(inputByteArray, 0, inputByteArray.Length);            cs.FlushFinalBlock();            StringBuilder ret = new StringBuilder();            foreach (byte b in ms.ToArray())            {                ret.AppendFormat("{0:X2}", b);            }            ret.ToString();            return ret.ToString().ToLower();                     }        public static string DESDeCode(string pToDecrypt)        {            //    HttpContext.Current.Response.Write(pToDecrypt + "<br>" + sKey);               //    HttpContext.Current.Response.End();               DESCryptoServiceProvider des = new DESCryptoServiceProvider();            byte[] inputByteArray = new byte[pToDecrypt.Length / 2];            for (int x = 0; x < pToDecrypt.Length / 2; x++)            {                int i = (Convert.ToInt32(pToDecrypt.Substring(x * 2, 2), 16));                inputByteArray[x] = (byte)i;            }            //des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);          //  des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);            des.Mode = CipherMode.ECB;            des.Key = ASCIIEncoding.UTF8.GetBytes(key);            des.IV = ASCIIEncoding.UTF8.GetBytes(key);            MemoryStream ms = new MemoryStream();            CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write);            cs.Write(inputByteArray, 0, inputByteArray.Length);            cs.FlushFinalBlock();            StringBuilder ret = new StringBuilder();            // return HttpContext.Current.Server.UrlDecode(System.Text.Encoding.Default.GetString(ms.ToArray()));            return System.Text.Encoding.UTF8.GetString(ms.ToArray());        }