IM仿照QQ做的即时通信，功能比较全

using System;
using System.Collections.Generic;
using System.Text;

namespace GGTalk
{
    /// 

    /// 3DES加密算法。可以直接使用其静态方法进行3DES加/解密。
    /// 

    public class Des3Encryption
    {
        #region Static
        /// 

        /// 使用3DES加密
        /// 
        
        public static byte[] Encrypt（byte[] origin string key）
        {
            Des3Encryption desEncryption = new Des3Encryption（key）;
            return desEncryption.Encrypt（origin）;
        }

        /// 

        /// 使用3DES解密
        /// 
 
        public static byte[] Decrypt（byte[] encrypted string key）
        {
            Des3Encryption desEncryption = new Des3Encryption（key）;
            return desEncryption.Decrypt（encrypted）;
        }

        /// 

        /// 使用3DES加密字符串
        /// 
  
        public static string EncryptString（string origin string key）
        {
            byte[] buff = System.Text.Encoding.UTF8.GetBytes（origin）;
            byte[] res = Des3Encryption.Encrypt（buff key）;
            return System.Text.Encoding.UTF8.GetString（res）;
        }

        /// 

        /// 使用3DES解密字符串
        /// 
 
        public static string DecryptString（string encrypted string key）
        {
            byte[] buff = System.Text.Encoding.UTF8.GetBytes（encrypted）;
            byte[] res = Des3Encryption.Decrypt（buff key）;
            return System.Text.Encoding.UTF8.GetString（res）;
        }
        #endregion

        #region member and search tables for des algorithms
        //define key Array
        private uint[][] keyArray = new uint[16][];
        //define many table for des algorithms
        #region tables for des encrypt
        private int[] fst_change_tb = {585042342618102605244362820124
                               625446383022146645648403224168
                               57494133251791595143352719113
                               615345372921135635547393123157};
        private int[] lst_change_tb = {408481656246432 397471555236331
                               386461454226230 375451353216129
                                364441252206028 353431151195927
                               342421050185826 33141949175725};
        private int[] mid_change_tb32 = {1672021 29122817 11523265183110
								 282414 3227391913306 2211425};
        private uint[] bits_tb64 = {0x800000000x400000000x200000000x10000000 0x8000000 
	                    0x4000000 0x2000000 0x1000000 0x800000 0x400000
                        0x200000 0x100000  0x80000 0x40000 0x200000x10000 
	                    0x8000 0x4000 0x2000 0x1000 0x800 0x400 0x200
	                    0x100 0x800x400x20 0x10 0x8 0x4 0x2 0x1
	              

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2019-01-02 15:46  即时通讯代码
     目录           0  2019-01-02 15:27  即时通讯代码Dlls
     文件     2866688  2017-11-14 09:02  即时通讯代码DllsAudioEngineCore.dll
     文件     1005056  2016-12-01 09:42  即时通讯代码DllsCSkin.dll
     文件      390656  2018-10-11 15:10  即时通讯代码DllsDataRabbit.dll
     文件      446976  2018-12-13 15:55  即时通讯代码DllsESBasic.dll
     文件      215220  2018-06-01 14:44  即时通讯代码DllsESBasic.xml
     文件      469504  2018-10-29 12:00  即时通讯代码DllsESframework.Boost.dll
     文件       82486  2017-11-14 10:53  即时通讯代码DllsESframework.Boost.xml
     文件     1164800  2019-01-02 10:32  即时通讯代码DllsESframework.dll
     文件      354881  2018-12-08 09:02  即时通讯代码DllsESframework.xml
     文件      440832  2014-08-29 01:11  即时通讯代码DllsMySql.Data.dll
     文件      334336  2018-11-20 09:54  即时通讯代码DllsOMCS.Boost.dll
     文件       39327  2018-11-20 09:45  即时通讯代码DllsOMCS.Boost.xml
     文件     2419200  2019-01-03 11:38  即时通讯代码DllsOMCS.dll
     文件      888302  2019-01-03 11:37  即时通讯代码DllsOMCS.xml
     文件      142336  2017-11-27 10:45  即时通讯代码DllsOMFile.dll
     文件      122880  2018-12-08 09:16  即时通讯代码DllsOraycn.MFile.dll
     文件       20302  2018-12-08 09:15  即时通讯代码DllsOraycn.MFile.xml
     文件     2380800  2016-12-01 09:42  即时通讯代码DllsSQLite.Interop.dll
     文件      282624  2016-12-01 09:42  即时通讯代码DllsSystem.Data.SQLite.dll
     文件      659456  2017-11-14 09:02  即时通讯代码DllsVideoEngineCore.dll
     文件    13496832  2012-12-06 15:38  即时通讯代码Dllsavcodec-53.dll
     文件      349696  2012-12-06 15:37  即时通讯代码Dllsavdevice-53.dll
     文件      890880  2012-12-06 15:37  即时通讯代码Dllsavfilter-2.dll
     文件     2462208  2012-12-06 15:38  即时通讯代码Dllsavformat-53.dll
     文件      137728  2012-12-06 15:37  即时通讯代码Dllsavutil-51.dll
     文件      121344  2017-11-14 09:02  即时通讯代码Dllsdxbase.dll
     文件      296960  2012-12-06 15:37  即时通讯代码Dllsswscale-2.dll
     目录           0  2017-11-28 17:33  即时通讯代码GGTalk
     目录           0  2017-11-28 17:35  即时通讯代码GGTalkControls
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