"Root"

"Root"

"Root(branch1/branch2) text(branch3/branch4)"

([^/()]*((?<=().*(?=)))[^/()]*)|([^/()]+)

"Root(branch1/branch2)"

"("

Regex.Matches

Regex.Matches

(?<=^|/)((?<br>()|(?<-br>))|[^()])*?(?(br)(?!))(?=$|/)

(?<=^(?(brb)(?!))(?:(?<-brb>()|(?<brb>))|[^()])*)
/
(?=(?:(?<bra>()|(?<-bra>))|[^()])*(?(bra)(?!))$)

List<string> Tokenize(strInput)
{
  var sb = new StringBuilder();
  var tokens = new List<string>();
  bool inParen = false;
  foreach(var c in strInput)
  {
      if (inParens)
      {
           if (c == ')')
               inParens = false;
           else
               sb.Append(c);
       }
       else if (c == '(')
               inParens = true;
       else if (c == '/')
            {
                 tokens.Add(sb.ToString());
                 sb.Length = 0;
            }
       else
             sb.Append(c);

  }
  if (sb.Length > 0)
      tokens.Add(sb.ToString());

  return tokens;
}

/((.+?)|[^/(]+)+/

/
(           # group things to be captured
  (.+?)   # 1 or more of anything in (escaped) brackets, un-greedily
|           # or ...
  [^/(]+   # 1 or more, not slash, and not open bracket characters
)+          # repeat until done...
/