C#的DNS协议完整实现代码

using Protocol.DomainNameSystem;
using Protocol.DomainNameSystem.Simple;
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;

namespace ConsoleApplication1
{
    class Program
    {

        static DnsPacket MyProcess（DnsPacket request）
        {
            if （request._3_4_OPCODE != DnsPacket.OPCODE_QUERY）
            {
                return null;
            }

            for （int i = 0; i < request.QDList.Count; i++）
            {
                if （request.QDList[i]._2_2_TYPE == DnsPacket.TYPE_A && request.QDList[i]._3_2_CLASS == DnsPacket.CLASS_IN &&
                    request.QDList[i].ResolveName（request）.ToLower（）.EndsWith（“.user.adsl001.com“））
                {
                    /*
                     * 根据域名查找IP。
                     */
                    string domian = request.QDList[i].ResolveName（request）;
                    UInt32 ttl = 10;    // 域名对应的IP失效时间，单位为秒，超过此时间后客户端应该重新发起查询。
                    string ip = “192.168.0.25“; // IP等会填到这里
                    // 你来写这一段，通过域名查找IP，从缓存里面去读，没有时间给你查数据库的。

                    /*
                     * 生成应答数据包。
                     */
                    DnsPacket response = new DnsPacket（）;
                    response._1_16_ID = request._1_16_ID;
                    response._2_1_QR = DnsPacket.QR_REPLY;
                    response._3_4_OPCODE = DnsPacket.OPCODE_QUERY;
                    response._4_1_AA = DnsPacket.AA_NON_AUTHORITATIVE_ANSWER;
                    response._5_1_TC = DnsPacket.TC_NON_TRUNCATION;
                    response._6_1_RD = DnsPacket.RD_NON_RECURSION_DESIRED;
                    response._7_1_RA = DnsPacket.RA_NON_RECURSION_AVAILABLE;
                    response._8_3_Z = 0;
                    response._9_4_RCODE = DnsPacket.RCODE_NO_ERROR;

                    DnsQuestion question = new DnsQuestion（）;
                    question._1_N_NAME = request.ResolveNameBytes（request.QDList[i]._1_N_NAME）;
                    question._2_2_TYPE = request.QDList[i]._2_2_TYPE;
                    question._3_2_CLASS = request.QDList[i]._3_2_CLASS;

                    response.QDList.Add（question）;
                    response._10_16_QDCOUNT = （UInt16）response.QDList.Count;

                    DnsResourceRecord record = new DnsResourceRecord（）;
                    record._1_N_NAME = request.ResolveNameBytes（request.QDList[i]._1_N_NAME）;
                    record._2_2_TYPE = DnsPacket.TYPE_A;
                    record._3_2_CLASS = DnsPacket.CLASS_IN;
                    record._4_4_TTL = ttl;
                    record._6_N_RDDATA = DnsHelper.FromIPString（ip）;
                    record._5_2_RDLENGTH = （UInt16）record._6_N_RDDATA.Length;

                    response.ANList.Add（record）;
                    response._11_16_ANCOUNT = （UInt16）response.ANList.Count;
                    
                    return response;
                }
            }