C#des加解密

C#
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//名称空间  
using  System;  
using  System.Security.Cryptography;  
using  System.IO;  
using  System.Text;  

//方法  
//加密方法  
public    string  Encrypt(string  pToEncrypt,  string  sKey)  
{  
           DESCryptoServiceProvider  des  =  new  DESCryptoServiceProvider();  
           //把字符串放到byte数组中  
                 //原来使用的UTF8编码，我改成Unicode编码了，不行  
           byte[]  inputByteArray  =  Encoding.Default.GetBytes(pToEncrypt);   


           //byte[]  inputByteArray=Encoding.Unicode.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);   

           //Write  the  byte  array  into  the  crypto  stream  
           //(It  will  end  up  in  the  memory  stream)