1.xml存储
2.链式结构存储
List<Node> nodes = new List<Node>()
{
new Node { ID = , Name = "中国" },
new Node { ID = , Name = "北京市", ParentID = },
new Node { ID = , Name = "吉林省", ParentID = },
new Node { ID = , Name = "上海市", ParentID = },
new Node { ID = , Name = "海淀区", ParentID = },
new Node { ID = , Name = "朝阳区", ParentID = },
new Node { ID = , Name = "大兴区", ParentID = },
new Node { ID = , Name = "白山市", ParentID = },
new Node { ID = , Name = "长春市", ParentID = },
new Node { ID = , Name = "抚松县", ParentID = },
new Node { ID = , Name = "靖宇县", ParentID = }
};