public void loaddataintreeview(List <eNhaCungCap> ncc, TreeView tv)
        {
            tv.Nodes.Clear();
            TreeNode n;

            foreach (eNhaCungCap tmp in nccbll.getAllNCC())
            {
                n     = new TreeNode(tmp.tenNCC);
                n.Tag = tmp.maNCC;
                tv.Nodes.Add(n);
            }
        }