using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Security.Cryptography;

using System.IO;

namespace DESHelper

{

    public class DESHelper

    {

        private static string m_encryptkey = "ENCRYPTT";

        private static string m_str = "IAMACOEDR";

        public static string DESEncrypt()

        {

            string str = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + m_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.Key = ASCIIEncoding.ASCII.GetBytes(m_encryptkey);

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

            MemoryStream ms = new MemoryStream();

            CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);

            cs.Write(inputByteArray, , 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 static string DESDecrypt(string pToDecrypt, string sKey)

        {

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            byte[] inputByteArray = new byte[pToDecrypt.Length / ];

            for (int x = ; x < pToDecrypt.Length / ; x++)

            {

                int i = (Convert.ToInt32(pToDecrypt.Substring(x * , ), ));

                inputByteArray[x] = (byte)i;

            }

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

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

            MemoryStream ms = new MemoryStream();

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

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

            cs.FlushFinalBlock();

            StringBuilder ret = new StringBuilder();

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

        }

        static void Main(string[] args)

        {

            string str = DESEncrypt();

            Console.WriteLine(str);

            Console.WriteLine(DESDecrypt(str, m_encryptkey));

        }

    }

}

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;

import javax.crypto.spec.IvParameterSpec;

import java.security.Key;

import java.security.spec.AlgorithmParameterSpec;

import javax.crypto.Cipher;

public class Des {

    //解密数据

    public static String decrypt(String message,String key) throws Exception {

        byte[] bytesrc =convertHexString(message);

        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.DECRYPT_MODE, secretKey, iv);

        byte[] retByte = cipher.doFinal(bytesrc);   

        return new String(retByte);

    }  

    // 加密数据

    public static byte[] encrypt(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"));

    }   

    public static byte[] convertHexString(String ss) {

        byte digest[] = new byte[ss.length() / 2];

        for(int i = 0; i < digest.length; i++) {

            String byteString = ss.substring(2 * i, 2 * i + 2);

            int byteValue = Integer.parseInt(byteString, 16);

            digest[i] = (byte)byteValue;

        }    

        return digest;

    }  

    public static String toHexString(byte b[]) {

        StringBuffer hexString = new StringBuffer();

        for (int i = 0; i < b.length; i++) {

            String plainText = Integer.toHexString(0xff & b[i]);

            if (plainText.length() < 2)

                plainText = "0" + plainText;

            hexString.append(plainText);

        }   

        return hexString.toString();

    }       

    public static void main(String[] args) throws Exception {

        String key = "ENCRYPTT";

        String value = "IAMACODER";

        String formatString = java.net.URLEncoder.encode(value, "utf-8");

        System.out.println("加密数据:"+ formatString);

        String encryptedString = toHexString(encrypt(formatString, key));

        System.out.println("加密后的数据为:" + encryptedString);

        String decryptedString = java.net.URLDecoder.decode(decrypt(encryptedString, key), "utf-8") ;

        System.out.println("解密后的数据:" + decryptedString);

    }

}