using System;

using System.Collections.Generic;

using System.Text.RegularExpressions;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var ResourceTypeRegex = new Regex(@"^(?: )?\((\w+)\)$");

        var value = " (HTML)";

        var match = ResourceTypeRegex.Match(value);

        Console.WriteLine("'" + match.Groups.ToList().FirstOrDefault() + "'");

​

    }

}

​

public static class RegexExtension

{

    public static List<string> ToList(this GroupCollection c) {

        var result = new List<string>();

        if (c.Count == 1) return result;

        //We only one index 1 and over since 0 is actually the entire string

        for(var i = 1; i < c.Count; i++) {

            result.Add(c[i].Value);

        }

        return result;

    }

}