C# 对称算法,加密解密类

来源：华军作者：若水 2008-04-23/10:19

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**************************************************************************/
using System.Text;
using System.IO;
using System;
using System.Text.RegularExpressions;
using System.Security.Cryptography;

namespace LHCHIP.Common
...{
    /**//// <summary>
    /// 对称加密算法类
    /// </summary>
    public class DecryptEncrypt
    ...{
        /**//// <summary>
        /// 返回自身的一个类
        /// </summary>
        public static DecryptEncrypt MyDecryptEncrypt
        ...{
            get
            ...{
                return new DecryptEncrypt();
            }
        }

_TempKey = _TempKey.Substring(0, KeyLength);
            else if (_TempKey.Length < KeyLength)
                _TempKey = _TempKey.PadRight(KeyLength, ’ ’);
            return ASCIIEncoding.ASCII.GetBytes(_TempKey);
        }
        /**//// <summary>
        /// 获得初始向量IV
        /// </summary>
        /// <returns>初试向量IV</returns>
        private byte[] GetLegalIV()
        ...{
            string _TempIV = "@afetj*Ghg7!rNIfsgr95GUqd9gsrb#GG7HBh(urjj6HJ($jhWk7&!hjjri%$hjk";
            mobjCryptoService.GenerateIV();
            byte[] bytTemp = mobjCryptoService.IV;
            int IVLength = bytTemp.Length;
            if (_TempIV.Length > IVLength)
                _TempIV = _TempIV.Substring(0, IVLength);
            else if (_TempIV.Length < IVLength)
                _TempIV = _TempIV.PadRight(IVLength, ’ ’);
            return ASCIIEncoding.ASCII.GetBytes(_TempIV);
        }

        /**//// <summary>
        /// 加密方法
        /// </summary>
        /// <param name="Source">待加密的串</param>
        /// <returns>经过加密的串</returns>
        public string Encrypto(string Source)
        ...{
            byte[] bytIn = UTF8Encoding.UTF8.GetBytes(Source);
            MemoryStream ms = new MemoryStream();
            mobjCryptoService.Key = GetLegalKey(); #p#分页标题#e#
            mobjCryptoService.IV = GetLegalIV();
            //创建对称加密器对象

private SymmetricAlgorithm mobjCryptoService;
        private string Key;

        /**//// <summary>
        /// 对称加密类的构造函数
        /// </summary>
        internal DecryptEncrypt()
        ...{
            mobjCryptoService = new RijndaelManaged();
            Key = "rrp(%&h70x89H$jgsfgfsI0456Ftma81&fvHrr&&76*h%(12lJ$lhj!y6&(*jkPer44a";
        }

        /**//// <summary>
        /// 获得密钥
        /// </summary>
        /// <returns>密钥</returns>
        private byte[] GetLegalKey()
        ...{
            string _TempKey = Key;
            mobjCryptoService.GenerateKey();
            byte[] bytTemp = mobjCryptoService.Key;
            int KeyLength = bytTemp.Length;
            if (_TempKey.Length > KeyLength)