public string Encrypt(string stringToEncrypt, string sKey)

    {

        DESCryptoServiceProvider des = new DESCryptoServiceProvider();

        byte[] inputByteArray = Encoding.GetEncoding("UTF-8").GetBytes(stringToEncrypt);

        des.Key = ASCIIEncoding.UTF8.GetBytes(sKey);

        des.IV = ASCIIEncoding.UTF8.GetBytes(sKey);

        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();

    }

    public string Decrypt(string stringToDecrypt, string sKey)

    {

        DESCryptoServiceProvider des = new DESCryptoServiceProvider();

        byte[] inputByteArray = new byte[stringToDecrypt.Length / 2];

        for (int x = 0; x < stringToDecrypt.Length / 2; x++)

        {

            int i = (Convert.ToInt32(stringToDecrypt.Substring(x * 2, 2), 16));

            inputByteArray[x] = (byte)i;

        }

        des.Key = ASCIIEncoding.UTF8.GetBytes(sKey);

        des.IV = ASCIIEncoding.UTF8.GetBytes(sKey);

        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 System.Text.Encoding.Default.GetString(ms.ToArray());

    }

 

 

//

 

publicsealedclass DESEncrypt

    ...{

        private DESEncrypt()

        ...{

            //

            // TODO: 在此处添加构造函数逻辑

            //

        }

        privatestaticstring key ="zhoufoxcn";

        /**////<summary>

        /// 对称加密解密的密钥

        ///</summary>

        publicstaticstring Key

        ...{

            get

            ...{

                return key;

            }

            set

            ...{

                key = value;

            }

        }

        /**////<summary>

        /// DES加密

        ///</summary>

        ///<param name="encryptString"></param>

        ///<returns></returns>

        publicstaticstring DesEncrypt(string encryptString)

        ...{

            byte[] keyBytes = Encoding.UTF8.GetBytes(key.Substring(0, 8));

            byte[] keyIV = keyBytes;

            byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);

            DESCryptoServiceProvider provider =new DESCryptoServiceProvider();

            MemoryStream mStream =new MemoryStream();

            CryptoStream cStream =new CryptoStream(mStream, provider.CreateEncryptor(keyBytes, keyIV), CryptoStreamMode.Write);

            cStream.Write(inputByteArray, 0, inputByteArray.Length);

            cStream.FlushFinalBlock();

            return Convert.ToBase64String(mStream.ToArray());

        }

        /**////<summary>

        /// DES解密

        ///</summary>

        ///<param name="decryptString"></param>

        ///<returns></returns>

        publicstaticstring DesDecrypt(string decryptString)

        ...{

            byte[] keyBytes = Encoding.UTF8.GetBytes(key.Substring(0, 8));

            byte[] keyIV = keyBytes;

            byte[] inputByteArray = Convert.FromBase64String(decryptString);

            DESCryptoServiceProvider provider =new DESCryptoServiceProvider();

            MemoryStream mStream =new MemoryStream();

            CryptoStream cStream =new CryptoStream(mStream, provider.CreateDecryptor(keyBytes, keyIV), CryptoStreamMode.Write);

            cStream.Write(inputByteArray, 0, inputByteArray.Length);

            cStream.FlushFinalBlock();

            return Encoding.UTF8.GetString(mStream.ToArray());

        }

    }