Operate xml to display xml data to treeview C# code

                foreach (XmlNode xn2 in )
                {
                    [i].();
                }
                i++;
            }
        }
        public void CreateXML()
        {
//Create an xml file
            XmlDeclaration dec = ("1.0", "utf-8", null);
            (dec);
//Add tree field
            XmlElement one = ("one");
            XmlElement two = ("two");
            XmlElement two1 = ("two");
            XmlElement three = ("three");
            XmlElement threeDL = ("three");
            XmlElement three1 = ("three");
            XmlElement three10 = ("three");
//Add tree structure relationship
            (one);
            (two);
            (two1);
            (three);
            (threeDL);
            (three1);
            (three10);
//Add attributes
("two", "Immortal");
("two", "dark night");
//Add content
            = "DK";
            = "DL";
            = "DH";
            = "WD";
            (@"D:\");
        }