public static void GetCollectionAnswerInfoFromHtml(string html, CollectionInfo ci)
        {
            if (!String.IsNullOrWhiteSpace(html))
            {
                try
                {
                    HtmlDocument doc = new HtmlDocument();
                    doc.LoadHtml(html);
                    HtmlNodeCollection answerNodes = doc.DocumentNode.SelectNodes(@"//div[@class='zm-item-rich-text js-collapse-body']");
                    foreach (HtmlNode answer in answerNodes)
                    {
                        string ids = answer.Attributes.FirstOrDefault(p => p.Name == "data-entry-url").Value;

                        string[] idsArr = ids.Split('/');
                        CollectionQuestionAndAnswer cqa = new CollectionQuestionAndAnswer()
                        {
                            CollectionID = ci.CollectionID,
                            QuestionID   = int.Parse(idsArr[2]),
                            AnswerID     = int.Parse(idsArr[4]),
                            ModefiedTime = DateTime.Now.ToString(),
                        };
                        CollectionDB.SaveOrUpdateCollectionAnswer(cqa);
                        Console.WriteLine("答案:" + cqa.AnswerID + " 于" + DateTime.Now.ToString() + "保存成功");
                    }
                }
                catch (Exception ex)
                {
                }
            }
        }
        public static bool SaveOrUpdateCollectionAnswer(CollectionQuestionAndAnswer cqa)
        {
            bool result = false;

            try
            {
                using (MainDataContext db = new MainDataContext())
                {
                    CollectionQuestionAndAnswer info = db.CollectionQuestionAndAnswers.FirstOrDefault(p => p.AnswerID == cqa.AnswerID);
                    if (info == null)
                    {
                        db.CollectionQuestionAndAnswers.InsertOnSubmit(cqa);
                    }
                    else
                    {
                        info = cqa;
                        info.ModefiedTime = DateTime.Now.ToString();
                    }
                    db.SubmitChanges();
                    result = true;
                }
            }
            catch (Exception ex)
            {
            }
            return(result);
        }