【C#正则基础】正则表达式

HtmlDocument htmldoc = new HtmlDocument();
            htmldoc.LoadHtml(htmltext);
            string htmldoctext = htmldoc.DocumentNode.InnerText;
            HtmlNode node = htmldoc.GetElementbyId("busi_success");
            string divtext = node.InnerHtml;
HtmlNodeCollection nodes = htmldoc.DocumentNode.SelectNodes("//table//tr//td");


//添加对Microsoft.mshtml这个程序集的引用，然后编写如下代码：
IHTMLDocument2 doc = new HTMLDocumentClass();
doc.write(new object[]{pageSource});
doc.close();
Title = doc.title;
Body = doc.body.innerText; 
public ArrayList GetMathList(string htmltext ,string pattern)



Public string GetFirstMathString(string htmltext,string pattern,bool isCut)

Public string GetFirstMathString(string htmltext,string pattern)

　　 　　/// <summary>
        /// 正则多匹配，返回匹配ArrayList数组
        /// </summary>
        /// <param name="htmltext">网页内容</param>
        /// <param name="pattern">模式字符串</param>
        /// <returns></returns>
        public ArrayList GetMathList(string htmltext, string pattern)
        {
            ArrayList list = new ArrayList();
            try
            {
                MatchCollection mc;
                //定义一个Regex对象实例 
                Regex regex = new Regex("(.*?)", RegexOptions.Singleline | RegexOptions.IgnoreCase);
                //或者多行匹配模式RegexOptions.Multiline  
                mc = regex.Matches(htmltext);
                //在输入字符串中找到所有匹配
                for (int i = 0; i < mc.Count; i++)
                {
                    //匹配一条信息就处理
                    string groupcode = mc[i].Value.ToString();
                    //处理函数
                    list.Add(groupcode);
                }
            }
            catch (Exception)
            {
                return null;
            }
            return list;
        }

//正则单匹配模式
Regex regex = new Regex("(.*?)", RegexOptions.Singleline);
                //text为要匹配的源字符串
                Match match = regex.Match(htmltext);
                //匹配成功，获取结果
                if (match.Success)
                {
                    string result1 = match.ToString();
                //对匹配出来的结果进行非目标值替换
                    string result2 = Regex.Replace(result1, "(.*?)","");
                    //rs是目标字符串
                    rs = Regex.Replace(result2, "(.*?)", "");
                }

　　　　　　　　　//正则多匹配模式
                MatchCollection mc;
                //定义一个Regex对象实例 
                Regex regex = new Regex("(.*?)", RegexOptions.Singleline | RegexOptions.IgnoreCase);
                //或者多行匹配模式RegexOptions.Multiline  
                mc = regex.Matches(groupcodeHtml);
                //在输入字符串中找到所有匹配
                for (int i = 0; i < mc.Count; i++)
                {
                    //匹配一条信息就处理
                    string groupcode = mc[i].Value.ToString();
                    //处理函数

                } 

　　　　 /// <summary>
        /// 正则表达式dan匹配方法
        /// </summary>
        /// <param name="htmltext">网页内容</param>
        /// <param name="pattern">模式字符串</param>
        /// <param name="result">返回匹配成功的字符串</param>
        /// <returns>匹配是否成功</returns>
        public static bool GetMatchStr(string htmltext, string pattern, out string result)
        {
            bool IsGetSuccess = false;
            result = "";
            try
            {
                string[] replaceStrs=new string[2];
                if (pattern.Contains("(.*?)"))
                {
                    string splitStr = pattern.Replace("(.*?)", "|");
                    replaceStrs = splitStr.Split('|');
                }
                Regex regex = new Regex(pattern, RegexOptions.Singleline | RegexOptions.IgnoreCase);
                Match match = regex.Match(htmltext);
                if (match.Success)
                {
                    result = match.ToString();
                    result = result.Replace(replaceStrs[0], "").Replace(replaceStrs[1], "");
                }
                else
                {
                    IsGetSuccess = false;
                }
            }
            catch (Exception ex)
            {
                IsGetSuccess = false;
            }
            finally
            {
                if (!string.IsNullOrEmpty(result))
                {
                    IsGetSuccess = true;
                }
                else
                {
                    IsGetSuccess = false;
                }
            }
            return IsGetSuccess;
        }