我在treeview   得doubleclick里写插入 代码,  
  执行的时候发现双击后有展开但马上又缩回去了,又加入treeview.selected.expand(true)也不行  
  除非点击node左边的+   否则展不开  
  请问怎么处理?   代码如下:
 private void treeView1_NodeMouseDoubleClick(object sender, TreeNodeMouseClickEventArgs e)
        {
            TreeNode node = this.treeView1.SelectedNode;
            if (node.Level == 0)
            {
                if (node.IsExpanded == false )
                {
                    node.SelectedImageIndex = 1;
                    node.ImageIndex = 1;
                     node.Expand();
                }
                if (node.IsExpanded == true)
                {
                    node.SelectedImageIndex = 0;
                    node.ImageIndex = 0;
                    node.Collapse();
                }
            }
        }恳请大家帮忙阿。