///   <summary>

         ///  异步分析下载

         ///   </summary>

         private   void  AsyncAnalyzeAndDownload( string  url,  string  savePath)

        {

             this .uriString  =  url;

             this .savePath  =  savePath;

             #region  分析计时开始

            count  =   0 ;

            count1  =   0 ;

            freq  =   0 ;

            result  =   0 ;

            QueryPerformanceFrequency( ref  freq);

            QueryPerformanceCounter( ref  count);

             #endregion

             using  (WebClient wClient  =   new  WebClient())

            {

                AutoResetEvent waiter  =   new  AutoResetEvent( false );

                wClient.Credentials  =  CredentialCache.DefaultCredentials;

                wClient.DownloadDataCompleted  +=   new  DownloadDataCompletedEventHandler(AsyncURIAnalyze);

                wClient.DownloadDataAsync( new  Uri(uriString), waiter);

                 // waiter.WaitOne();      // 阻止当前线程，直到收到信号

            }

                

        }

         ///   <summary>

         ///  异步分析

         ///   </summary>

         protected   void  AsyncURIAnalyze(Object sender, DownloadDataCompletedEventArgs e)

        {

            AutoResetEvent waiter  =  (AutoResetEvent)e.UserState;

             try

            {

                 if  ( ! e.Cancelled  &&  e.Error  ==   null )

                {

                    

                     string  dnDir  =   string .Empty;

                     string  domainName  =   string .Empty;

                     string  uri  =  uriString;

                     // 获得域名  http://www.sina.com/

                    Match match  =  Regex.Match(uri,  @" ((http(s)?://)?)+[\w-.]+[^/] " ); // , RegexOptions.IgnoreCase

                    domainName  =  match.Value;

                     // 获得域名最深层目录  http://www.sina.com/mail/

                     if  (domainName.Equals(uri))

                        dnDir  =  domainName;

                     else

                        dnDir  =  uri.Substring( 0 , uri.LastIndexOf( ' / ' ));

                    dnDir  +=   ' / ' ;

                    

                     // 获取数据

                     string  pageData  =  Encoding.UTF8.GetString(e.Result);

                    List < string >  urlList  =   new  List < string > ();

                     // 匹配全路径

                    match  =  Regex.Match(pageData,  @" ((http(s)?://)?)+(((/?)+[\w-.]+(/))*)+[\w-./]+\.+( "   +  ImageType  +   " ) " );  // , RegexOptions.IgnoreCase

                     while  (match.Success)

                    {

                         string  item  =  match.Value;

                         // 短路径处理

                         if  (item.IndexOf( " http:// " )  ==   - 1   &&  item.IndexOf( " https:// " )  ==   - 1 )

                            item  =  (item[ 0 ]  ==   ' / '   ?  domainName : dnDir)  +  item;

                         if  ( ! urlList.Contains(item))

                        {

                            urlList.Add(item);

                            imgUrlList.Add(item);

                             // 实时显示分析结果

                            AddlbShowItem(item);

                             // 边分析边下载

                            WebRequest hwr  =  WebRequest.Create(item);

                            hwr.BeginGetResponse( new  AsyncCallback(AsyncDownLoad), hwr);

                             // hwr.Timeout = "0x30D40";         // 默认 0x186a0 -> 100000 0x30D40 -> 200000

                             // hwr.Method = "POST";

                             // hwr.ContentType = "application/x-www-form-urlencoded";

                             // hwr.MaximumAutomaticRedirections = 3;

                             // hwr.Accept ="image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*";

                             // hwr.Accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, */*";

                             // IAsyncResult iar = hwr.BeginGetResponse(new AsyncCallback(AsyncDownLoad), hwr);

                             // iar.AsyncWaitHandle.WaitOne();

                        }

                        match  =  match.NextMatch();

                    }

                }

            }

             finally

            {

                waiter.Set();

                 #region  分析计时结束

                QueryPerformanceCounter( ref  count1);

                count  =  count1  -  count;

                result  =  ( double )(count)  /  ( double )freq;

                toolStripStatusLabel1.Text  =   " 分析完毕！ " ;

                toolStripStatusLabel2.Text  =   string .Format( "  | 分析耗时:{0}秒 " , result);

                Application.DoEvents();

                 #endregion

                 // 分析完毕

                isAnalyzeComplete  =   true ;

            }

        }

         ///   <summary>

         ///  异步接受数据

         ///   </summary>

         ///   <param name="asyncResult"></param>

         public    void  AsyncDownLoad(IAsyncResult asyncResult)  

        {

             #region  下载计时开始

             if  (cfreq  ==   0 )

            {

                QueryPerformanceFrequency( ref  cfreq);

                QueryPerformanceCounter( ref  ccount);

            }

             #endregion

            WebRequest request  =  (WebRequest)asyncResult.AsyncState;

             string  url  =  request.RequestUri.ToString();

             try

            {

                WebResponse response  =  request.EndGetResponse(asyncResult);

                 using  (Stream stream  =  response.GetResponseStream())

                {

                    Image img  =  Image.FromStream(stream);

                     string [] tmpUrl  =  url.Split( ' . ' );

                    img.Save( string .Concat(savePath,  " / " , DateTime.Now.ToString( " yyyyMMddHHmmssfff " ),  " . " , tmpUrl[tmpUrl.Length  -   1 ]));

                    img.Dispose();

                    stream.Close();

                }

                allDone.Set();

                 // 从未下载的列表中删除已经下载的图片

                imgUrlList.Remove(url);

                 // 更新列表框

                 int  indexItem  =   this .lbShow.Items.IndexOf(url);

                 if  (indexItem  >=   0   &&  indexItem  <=   this .lbShow.Items.Count)

                    SetlbShowItem(indexItem);

            }

             catch  (Exception)

            {

                imgUrlList.Remove(url);

            }

        }