C# 正则提取字符串（提取一个或多个）

实例一：
string result = "";

            string str = "大家好! <User EntryTime='2010-10-7' Email='[email protected]'>张三</User> 自我介绍。";

            Regex regex = new Regex(@"<User\s*EntryTime='(?<time>[\s\S]*?)'\s+Email='(?<email>[\s\S]*?)'>(?<userName>[\s\S]*?)</User>", RegexOptions.IgnoreCase);

            Match match = regex.Match(str);

            if (match.Success)

            {

                string userName = match.Groups["userName"].Value; //获取用户名

                string time = match.Groups["time"].Value; //获取入职时间

                string email = match.Groups["email"].Value; //获取邮箱地址

                string strFormat = String.Format("我是：{0}，入职时间：{1}，邮箱：{2}", userName, time, email);

                result = regex.Replace(str, strFormat); //替换内容

                Console.WriteLine(result);

            }

实例二：

            var s = "http://www.baidu.com/articles/2018/3/15/sss.html";

            var reg = new Regex(@"articles/(?<date>\d{4}/\d{1,2}/\d{1,2})/", RegexOptions.IgnoreCase);

            Match _match = reg.Match(s);

            if (_match.Success)

            {

                Console.WriteLine(_match.Groups["date"]);

            }