import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;

public class Des {
    private byte[] desKey;

    //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);
    }

    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 void main(String[] args) throws Exception {
        String key = "11111111";
        String value="aa";
        String jiami=java.net.URLEncoder.encode(value, "utf-8").toLowerCase();

        System.out.println("加密数据:"+jiami);
        String a=toHexString(encrypt(jiami, key)).toUpperCase();

        System.out.println("加密后的数据为:"+a);
        String b=java.net.URLDecoder.decode(decrypt(a,key), "utf-8") ;
        System.out.println("解密后的数据:"+b);
    }

    public static String toHexString(byte b[]) {
        StringBuffer hexString = new StringBuffer();
        for (int i = 0; i < b.length; i++) {
            String plainText = Integer.toHexString(0xff &amp; b[i]);
            if (plainText.length() < 2)
                plainText = "0" + plainText;
            hexString.append(plainText);
        }

        return hexString.toString();
    }

}
  

using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

using System.Configuration;
using System.Web;
using System.Security.Cryptography;
using System.IO;

namespace DES
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string jiami = textBox1.Text;
            textBox2.Text= DESEnCode(jiami, "11111111");
        }

        public static string DES_Key = "11111111";

        #region DESEnCode DES加密
        public static string DESEnCode(string pToEncrypt, string sKey)
        {
            // string pToEncrypt1 = HttpContext.Current.Server.UrlEncode(pToEncrypt);
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] inputByteArray = Encoding.GetEncoding("UTF-8").GetBytes(pToEncrypt);

            //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(sKey);
            des.IV = ASCIIEncoding.ASCII.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();
        }
        #endregion

        #region DESDeCode DES解密
        public static string DESDeCode(string pToDecrypt, string sKey)
        {
            //    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);
            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.Default.GetString(ms.ToArray());
        }
        #endregion

        private void button2_Click(object sender, EventArgs e)
        {
            string jiemi = textBox2.Text;
            textBox3.Text = DESDeCode(jiemi,"11111111");
        }
    }
}