c# asp.net 字符串加密解密的类

using System;   
using System.Collections.Generic;   
using System.Text;   
using System.Security.Cryptography;//Cryptography密码术   
namespace DAL   
{   
    public class Encry   
    {   
        public Encry() { }  
 
        #region AES加密   
  
        public static string Encrypt(string toEncrypt)   
        {   
            byte[] keyArray = UTF8Encoding.UTF8.GetBytes("12345678901234567890123456789012");   
            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);   
  
            RijndaelManaged rDel = new RijndaelManaged();//using System.Security.Cryptography;   
            rDel.Key = keyArray;   
            rDel.Mode = CipherMode.ECB;//using System.Security.Cryptography;   
            rDel.Padding = PaddingMode.PKCS7;//using System.Security.Cryptography;   
  
            ICryptoTransform cTransform = rDel.CreateEncryptor();//using System.Security.Cryptography;   
     &nbs