public static void GetQuestionInfoFormHtml(string HtmlStr)
 {
     if (!String.IsNullOrEmpty(HtmlStr))
     {
         HtmlDocument doc = new HtmlDocument();
         doc.LoadHtml(HtmlStr);
         HtmlNodeCollection questionItems = doc.DocumentNode.SelectNodes(@"//div[@class='feed-item feed-item-hook question-item']");
         if (questionItems != null && questionItems.Count > 0)
         {
             foreach (HtmlNode node in questionItems)
             {
                 try
                 {
                     HtmlNode subTopic = node.SelectNodes(@"div[@class='subtopic']//a").ToList()[0];
                     HtmlNode titleNode = node.SelectNodes(@"h2[@class='question-item-title']").ToList()[0];
                     string subtopicId = "";
                     string timeStamp = "";
                     string title = "";
                     string questionId = "";
                     subtopicId = subTopic.Attributes.FirstOrDefault(p => p.Name == "href").Value;
                     string[] topic = subtopicId.Split('/');
                     subtopicId = topic[2];
                     timeStamp = titleNode.SelectNodes(@"span").ToList()[0].Attributes.FirstOrDefault(p => p.Name == "data-timestamp").Value;
                     questionId = titleNode.SelectNodes(@"a").ToList()[0].Attributes.FirstOrDefault(p => p.Name == "href").Value;
                     title = titleNode.SelectNodes(@"a").ToList()[0].InnerText;
                     string[] question = questionId.Split('/');
                     foreach (var j in question)
                     {
                         questionId = question[2];
                     }
                     QuestionInfo qi = new QuestionInfo();
                     qi.QuestionID = int.Parse(questionId);
                     qi.QuestionTitle = title;
                     qi.QuestionTimeStamp = long.Parse(timeStamp);
                     qi.BelongsTopic = subtopicId;
                     qi.ModefiedTime = DateTime.Now.ToString();
                     qi.QuestionUrl = @"http://www.zhihu.com/question/" + qi.QuestionID;
                     if (QuestionInfoDB.SaveOrUpdateQuestionInfo(qi))
                     {
                         Console.WriteLine("问题:" + qi.QuestionID + " " + qi.QuestionTitle + " 于 " + qi.ModefiedTime + " 保存完成");
                     }
                     else
                     {
                         Console.WriteLine("问题:" + qi.QuestionID + " " + qi.QuestionTitle + " 于 " + qi.ModefiedTime + " 保存失败");
                     }
                 }
                 catch (Exception ex)
                 {
                 }
             }
             DownLoadCount += 1;
             if (DownLoadCount % 10 == 0)
             {
                 SysDictDB.SaveOrUpdateDownLoadPageCount(DownLoadCount);
             }
             Thread.Sleep(1000 * 5);
         }
     }
 }
 public static bool DeleteQuestionInfo(QuestionInfo qi)
 {
     bool result = false;
     try
     {
         if (qi != null)
         {
             using (MainDataContext db = new MainDataContext())
             {
                 QuestionInfo Info = db.QuestionInfos.FirstOrDefault(p => p.QuestionID == qi.QuestionID);
                 if (Info != null)
                 {
                     db.QuestionInfos.DeleteOnSubmit(Info);
                 }
                 db.SubmitChanges();
                 result = true;
             }
         }
     }
     catch (Exception ex)
     {
     }
     return result;
 }
 partial void DeleteQuestionInfo(QuestionInfo instance);
 partial void UpdateQuestionInfo(QuestionInfo instance);
 partial void InsertQuestionInfo(QuestionInfo instance);
 partial void DeleteQuestionInfo(QuestionInfo instance);
 partial void UpdateQuestionInfo(QuestionInfo instance);
 partial void InsertQuestionInfo(QuestionInfo instance);
 public static bool SaveOrUpdateQuestionInfo(QuestionInfo qi)
 {
     bool result = false;
     try
     {
         using (MainDataContext db = new MainDataContext())
         {
             QuestionInfo Info = db.QuestionInfos.FirstOrDefault(p => p.QuestionID == qi.QuestionID);
             if (Info == null)
             {
                 db.QuestionInfos.InsertOnSubmit(qi);
             }
             else
             {
                 Info = qi;
             }
             db.SubmitChanges();
             result = true;
         }
     }
     catch (Exception ex)
     {
     }
     return result;
 }