string url = "http://www.114369.com";

        string html = MyCLib.NetClass.SendUrl(url,System.Text.Encoding.UTF8);

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

        Regex reg = new Regex(@"(?is)<a[^>]*?href=(['""]?)(?<url>[^'""\s>]+)\1[^>]*>(?<text>(?:(?!</?a\b).)*)</a>");

        MatchCollection mc = reg.Matches(html);

        foreach (Match m in mc)

        {

            //richTextBox2.Text += m.Groups["url"].Value + "\n";

            string keyword = Regex.Replace(m.Groups["text"].Value, "<[^>]*>", string.Empty).Replace("..", "").Replace("·", "").Replace("&nbsp;", "");

            if (keyword.Length >  && !keywords.Contains(keyword))

            {

                keywords.Add(keyword);

            }

        }

        for (int i = ; i < keywords.Count; i++)

        {

            Response.Write(keywords[i]);

            Response.Write("<br>");

        }

string s = "<a href=\"#\">我们是中国人</a><a class='xxx' href=\"#\">我们是中国人2</a>";

        Regex reg = new Regex(@"<a\s*[^>]*>([\s\S]+?)</a>", RegexOptions.IgnoreCase);

        s = reg.Replace(s, "$1");

        Response.Write(s);//结果：我们是中国人我们是中国人2

string s = "<a href=\"#\">我们是中国人</a><a class='xxx' href=\"#\">我们是中国人2</a>";

s = s.replace(/(<\/?a[^>]*>)(?!.*\)/ig,"");