如何打造网站克隆、仿站工具（C#版）

interface iwebcloneworker
    {
        void start();
        void cancel();
    }

public class webcloneworker : iwebcloneworker
    {
        //网站页面克隆深度(如：0-首页,1-分类页,2-详细页面)
        public static int depth = 0;
        
        //要克隆的网站网址
        public string url { get; set; }

        //克隆后，保存的路径
        public string savepath { get; set; }

        private backgroundworker backgroundworker1 = null;
        public event urlchangedeventhandler urlchanged;
        public event filesavedsuccesseventhandler filesavedsuccess;
        public event filesavedfaileventhandler filesavedfail;
        public event downloadcompletedeventhandler downloadcompleted;
        public event collectingurleventhandler collectingurl;
        public event collectedurleventhandler collectedurl;
        public event progresschangedeventhandler progresschanged;

        //所有页面、文件资源地址集合
        private dictionary<string, urlmodel> _hrefs = new dictionary<string, urlmodel>();

        /// <summary>
        /// 所有页面、文件资源地址集合
        /// </summary>
        public dictionary<string,urlmodel> hrefs
        {
            get { return _hrefs; }
            set { _hrefs = value; }
        }

        //网站页面请求编码,默认为utf-8
        private string _encoding = "utf-8";

        //网站页面请求编码,默认为utf-8
        public string encoding
        {
            get { return _encoding; }
            set { _encoding = value; }
        }

        public webcloneworker() { }

        public webcloneworker(string url,string path) 
        {
            //设置网站、保存路径
            this.url = url;
            this.savepath = path;

            if (string.isnullorempty(this.url))
                throw new exception("请输入网址");

            if (string.isnullorempty(this.savepath))
                throw new exception("请选择要保存的目录");

            backgroundworker1 = new backgroundworker();

            //设置报告进度更新
            backgroundworker1.workerreportsprogress = true;
            backgroundworker1.workersupportscancellation = true;

            //注册线程主体方法
            backgroundworker1.dowork += backgroundworker1_dowork;

            //注册更新ui方法
            backgroundworker1.progresschanged += backgroundworker1_progresschanged;

            //处理完毕
            backgroundworker1.runworkercompleted += backgroundworker1_runworkercompleted;
        }

        void backgroundworker1_runworkercompleted(object sender, runworkercompletedeventargs e)
        {
            if (e.cancelled) {
                return;
            }

            if (this.downloadcompleted != null)
            {
                downloadcompletedeventargs eventargs = new downloadcompletedeventargs(e.result, e.error, e.cancelled);
                this.downloadcompleted(this, eventargs);
            }
        }

        void backgroundworker1_progresschanged(object sender, progresschangedeventargs e)
        {
            //进度回调
            if (this.progresschanged != null) 
                this.progresschanged(this, e);

            urlmodel model = (urlmodel)e.userstate;

            if (this.urlchanged != null)
            {
                //url改变后，回调
                urlchangedeventargs eventargs = new urlchangedeventargs(model);
                this.urlchanged(this, eventargs);
            }

            try
            {
                string dir = this.savepath;
                string url = model.absoluteuri;
                string absolutepath = url.substring(url.indexof('/', 8));
                string filename = "";

                if (url.indexof('?') > 0)
                {
                    string path = absolutepath.substring(0, model.relatedpath.indexof('?'));
                    filename = system.io.path.getfilename(path);
                }
                else
                {
                    filename = system.io.path.getfilename(absolutepath);
                }

                //默认首页
                if (string.isnullorempty(filename) || filename.indexof(".") < 0)
                {
                    filename = "";

                    if (!absolutepath.endswith("/"))
                        absolutepath = absolutepath + "/";
                }

                filename = system.web.httputility.urldecode(filename);

                string localpath = string.format("{0}{1}", dir, system.io.path.getdirectoryname(absolutepath));
                if (!system.io.directory.exists(localpath))
                {
                    system.io.directory.createdirectory(localpath);
                }

                //判断文件是否存在，存在不再下载
                string path2 = path.combine(localpath, filename);
                if (file.exists(path2))
                {
                    return;
                }

                //下载网页、图片、资源文件
                httptool.downfile(url, localpath, filename);

                //保存成功后，回调
                if (this.filesavedsuccess != null)
                {
                    filesavedsuccesseventargs eventargs = new filesavedsuccesseventargs(model);
                    this.filesavedsuccess(this, eventargs);
                }
            }
            catch (exception ex)
            {
                //保存失败后，回调
                if (this.filesavedfail != null)
                {
                    filesavedfaileventargs eventargs = new filesavedfaileventargs(ex);
                    this.filesavedfail(this, eventargs);
                }
            }
        }

        void backgroundworker1_dowork(object sender, doworkeventargs e)
        {
            //获取资源
            getresource();

            int index = 1;
            if (this.hrefs.keys.count > 0)
            {
                foreach (var k in this.hrefs.keys)
                {
                    //取消操作
                    if (backgroundworker1.cancellationpending)
                    {
                        e.cancel = true;
                        return;
                    }

                    backgroundworker1.reportprogress(index, this.hrefs[k]);
                    index++;

                    //挂起当前线程200毫秒
                    thread.sleep(200);
                }
            }
        }

        public void start()
        {
            if (this.backgroundworker1.isbusy)
                return;

            this.backgroundworker1.runworkerasync();
        }

        public void cancel()
        {
            if (this.backgroundworker1.cancellationpending)
                return;

            this.backgroundworker1.cancelasync();
        }
        
        private void getresource()
        {
            string url = this.url;
            string referer = this.url;
            string msg = "";
            string html = httptool.httpget(url, referer, this.encoding, out msg);

            //收集页面链接
            gethrefs(0, url, html);

            //收集完毕
            if (null != collectedurl)
            {
                urlmodel urlmodel = new urlmodel();
                collectedurleventargs eventargs = new collectedurleventargs(urlmodel);
                this.collectedurl(this, eventargs);
            }

        }

        private void gethrefs(int level,string url,string html)
        {
            #region 添加当前页

            urlmodel currurl = urlparser.parse(url);

            try
            {
                //取消
                if (backgroundworker1.cancellationpending)
                    return;

                this.hrefs.add(currurl.relatedpath, currurl);

                //收集回调
                if (null != collectingurl)
                {
                    collectingurleventargs eventargs = new collectingurleventargs(currurl);
                    this.collectingurl(this, eventargs);
                }
            }
            catch
            {
            }

            #endregion

            //获取相关链接(含有href属性的)
            list<urlmodel> list1 = webpageservice.getlocalhrefs(url,html);

            //获取图片，文件等资源文件(含有src属性的)
            list<urlmodel> listsrcs = webpageservice.getlocalsrcs(url,html);

            #region 获取当级资源文件

            if (listsrcs != null)
            {
                for (int i = 0; i < listsrcs.count; i++)
                {
                    urlmodel urlmodel = listsrcs[i];
                    try
                    {
                        //取消
                        if (backgroundworker1.cancellationpending) 
                            return;

                        this.hrefs.add(urlmodel.relatedpath, urlmodel);

                        //收集回调
                        if (null != collectingurl)
                        {
                            collectingurleventargs eventargs = new collectingurleventargs(urlmodel);
                            this.collectingurl(this, eventargs);
                        }
                    }
                    catch
                    { }
                }
            }

            #endregion

            #region 获取子级页面资源

            //获取第二级
            if (list1 != null)
            {
                for (int i = 0; i < list1.count; i++)
                {
                    urlmodel urlmodel = list1[i];

                    try
                    {
                        //取消
                        if (backgroundworker1.cancellationpending)
                            return;

                        this.hrefs.add(urlmodel.relatedpath, urlmodel);

                        //收集回调
                        if (null != collectingurl)
                        {
                            collectingurleventargs eventargs = new collectingurleventargs(urlmodel);
                            this.collectingurl(this, eventargs);
                        }
                    }
                    catch
                    { }

                    string msg = "";
                    html = httptool.httpget(urlmodel.absoluteuri, urlmodel.absoluteuri, this.encoding, out msg);

                    #region 获取子级资源文件

                    /*
                     * 获取二级资源文件
                     * */
                    listsrcs = webpageservice.getlocalsrcs(urlmodel.absoluteuri, html);//资源文件

                    if (listsrcs != null)
                    {
                        for (int j = 0; j < listsrcs.count; j++)
                        {
                            urlmodel urlmodel2 = listsrcs[j];

                            try
                            {
                                //取消
                                if (backgroundworker1.cancellationpending)
                                    return;

                                this.hrefs.add(urlmodel2.relatedpath, urlmodel2);

                                //收集回调
                                if (null != collectingurl)
                                {
                                    collectingurleventargs eventargs = new collectingurleventargs(urlmodel2);
                                    this.collectingurl(this, eventargs);
                                }
                            }
                            catch
                            { }

                            //挂起线程20毫秒
                            thread.sleep(20);
                        }
                    }
                    #endregion

                    //挂起线程20毫秒
                    thread.sleep(20);

                    //到达指定深度后，退出
                    if (level >= depth)
                        return;

                    //递归
                    gethrefs(level + 1, urlmodel.absoluteuri, html);
                }
            }

            #endregion
        }
    }

public delegate void urlchangedeventhandler(object sender, urlchangedeventargs e);
    public delegate void filesavedsuccesseventhandler(object sender, filesavedsuccesseventargs e);
    public delegate void filesavedfaileventhandler(object sender, filesavedfaileventargs e);
    public delegate void downloadcompletedeventhandler(object sender, downloadcompletedeventargs e);
    public delegate void collectingurleventhandler(object sender, collectingurleventargs e);
    public delegate void collectedurleventhandler(object sender, collectedurleventargs e);
    public delegate void progresschangedeventhandler(object sender, progresschangedeventargs e);

public class collectedurleventargs : eventargs
public class collectingurleventargs : eventargs
public class downloadcompletedeventargs : eventargs
public class filesavedfaileventargs : eventargs
public class filesavedsuccesseventargs : eventargs
public class urlchangedeventargs : eventargs