import javax.crypto.*;

import javax.crypto.*;

import java.io.UnsupportedEncodingException;

import java.security.spec.*;

import javax.crypto.spec.*;

public class DES {

    public DES()

    {

    }

     public String encrypt(String str) {

        byte[] enc = null;

        try {

          enc = desEncrypt(str, "abcdefgh");

        }

        catch (Exception ex) {

        }

         return new sun.misc.BASE64Encoder().encode(enc);

     }

     public static byte[] desEncrypt(String message, String key) throws Exception {

             Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");

             DESKeySpec desKeySpec = new DESKeySpec(key.getBytes("UTF-8"));

             SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");

             SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

             IvParameterSpec iv = new IvParameterSpec(key.getBytes("UTF-8"));

             cipher.init(Cipher.ENCRYPT_MODE, secretKey, iv);

             return cipher.doFinal(message.getBytes("UTF-8"));

         }

}

    /// <param name="pToDecrypt">要解密的以Base64</param>

        /// <param name="sKey">密钥，且必须为8位。</param>

        /// <returns>已解密的字符串。</returns>

        public string Decrypt(string pToDecrypt, string sKey)

        {

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

            using (DESCryptoServiceProvider des = new DESCryptoServiceProvider())

            {

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

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

                System.IO.MemoryStream ms = new System.IO.MemoryStream();

                using (CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(), CryptoStreamMode.Write))

                {

                    cs.Write(inputByteArray, , inputByteArray.Length);

                    cs.FlushFinalBlock();

                    cs.Close();

                }

                string str = Encoding.UTF8.GetString(ms.ToArray());

                ms.Close();

                return str;

            }

        }