public static class Decryption
    {
        private static byte[] key = { 0x21, 0x43, 0x65, 0x87, 0x09, 0xBA, 0xDC, 0xFE };
        private static byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

        /// <summary>
        /// 加密处理
        /// </summary>
        /// <param name="Input"></param>
        /// <returns></returns>
        public static string Encrypt(string Input)
        {
            try
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                Byte[] inputByteArray = Encoding.UTF8.GetBytes(Input);
                MemoryStream ms = new MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(key, IV), CryptoStreamMode.Write);
                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                return Convert.ToBase64String(ms.ToArray());
            } catch (Exception ex)
            {
                return "";
            }
        }

        /// <summary>
        /// 解密处理
        /// </summary>
        /// <param name="Input"></param>
        /// <returns></returns>
        public static string Decrypt(string Input)
        {
            if (!string.IsNullOrEmpty(Input))
            {
                Input = Input.Replace(" ", "+");
                Byte[] inputByteArray = new Byte[Input.Length];
                try
                {
                    DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                    inputByteArray = Convert.FromBase64String(Input);
                    MemoryStream ms = new MemoryStream();
                    CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(key, IV), CryptoStreamMode.Write);
                    cs.Write(inputByteArray, 0, inputByteArray.Length);
                    cs.FlushFinalBlock();
                    Encoding encoding = Encoding.UTF8;
                    return encoding.GetString(ms.ToArray());
                } catch (Exception ex)
                {
                    return "";
                }
            } else
            {
                return "";
            }
        }
    }

        /// <summary>
        /// 替换email中的字符串
        /// </summary>
        /// <returns></returns>
        public static String getEmailStr(string url,string userName, string s_key)
        {
            //s_key为随机生成的字符串
            String str = userName+ "," +s_key;

            return "<a href=\"" + url + "?" + Decryption.Encrypt(str) + "\"></a>";
        }

                try
                {
                    param = Request.Url.Query;
                    param = param.Substring(1, param.