using System;
using System.Text.RegularExpressions;

class Example 
{
   static void match(string pat, string text)
   {
      // Instantiate the regular expression object.
      Regex r = new Regex(pat, RegexOptions.IgnoreCase);

      // Match the regular expression pattern against a text string.
      Match m = r.Match(text);
      int matchCount = 0;
      while (m.Success) 
      {
         Console.WriteLine("Match"+ (++matchCount));
         for (int i = 1; i <= 3; i++) 
         {
            Group g = m.Groups[i];
            Console.WriteLine("Group" + i + " = '" + g + "'");
         }
         m = m.NextMatch();
      }
   }
   static void Main() 
   {
      string pat = @"(?:(<div id[^>]+>)(\w+))?([\ _]{3,})";
      match(pat, "<div id=\"div1\">Street ___________________ </div>");
      match(pat, "<div id=\"div2\">CAP |__|__|__|__|__| number ______ </div>");
      match(pat, "<div id=\"div3\">City _____________________ State |__|__|</div>");
      match(pat, "<div id=\"div4\">City2 ____________________ State2 _____</div>");
   }
}