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='zhangsan@163.com'>张三</User> 自我介绍。";
            Regex regex = new Regex(@"<Users*EntryTime='(?<time>[sS]*?)'s+Email='(?<email>[sS]*?)'>(?<userName>[sS]*?)</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"]);
            }