bool flag = true;
        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.Load(Server.MapPath("~/test.xml"));
        XmlNodeList nodes = xmlDoc.SelectNodes(@"//X");
        foreach (XmlNode node in nodes)
        {
            if (node.SelectSingleNode(@".//E") == null)
            {
                flag = false;
                break;
            }
        }
        Response.Write(flag);