public static string GetQuestionLevelIndex(QuestionNode node) { List <string> strList = new List <string>(); do { strList.Add((node.Index + 1).ToString()); node = (QuestionNode)node.Parent; } while (node != null); string str = ""; for (int i = strList.Count - 1; i >= 0; i--) { str += strList[i]; if (i > 0) { str += "."; } } return(str); }