Microsoft.JScript.RegExpConstructor.GetMemberValue C# (CSharp) Method

      internal override Object GetMemberValue(String name) {
        if (name.Length == 2 && name[0] == '$') {
          char ch = name[1];
          switch (ch) {
            case '1': case '2': case '3':
            case '4': case '5': case '6':
            case '7': case '8': case '9': {
              if (this.lastRegexMatch == null)
                return "";
              Group group = this.lastRegexMatch.Groups[ch.ToString()];
              return group.Success ? group.ToString() : "";
            }
            case '`':
              return this.GetLeftContext();
            case '\'':
              return this.GetRightContext();
            case '&':
              return this.GetLastMatch();
            case '+':
              return this.GetLastParen();
            case '_':
              return this.GetInput();
          }
        }
        return base.GetMemberValue(name);
      }