同步TreeView中父结点和子结点的状态[以及Treeview的bug]

此代码仅仅是二级结点，即父结点下面只有一层子结点,只有两层结构

        /// <summary>
        /// 某个结点的CheckBox被选中
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void treeViewDevices_AfterCheck(object sender, TreeViewEventArgs e)
        {
            //将父结点的状态同步给子结点
            setChildNodeCheckedState(e.Node,e.Node.Checked);

            if (e.Node.Parent != null)
            {
                setParentNodeCheckedState(e.Node);
            }

        }

        /// <summary>
        /// 选中结点之后,自动选择当前结点所有的子结点
        /// </summary>
        /// <param name="currNode">当前结点</param>
        /// <param name="state">选中状态</param>
        private void setChildNodeCheckedState(TreeNode currNode, bool state)
        {
            TreeNodeCollection nodes = currNode.Nodes;
            foreach (TreeNode tn in nodes)
            {
                tn.Checked = state;
                setChildNodeCheckedState(tn, state);
            }
        }

        /// <summary>
        /// 选中当前结点之后,设置父结点的状态
        /// </summary>
        /// <param name="currNode"></param>
        private void setParentNodeCheckedState(TreeNode currNode)
        {
            if (currNode.Checked)//当前结点为选中状态
            {
                if (currNode.Parent.Checked==false)
                {
                    treeViewDevices.AfterCheck -= new System.Windows.Forms.TreeViewEventHandler(this.treeViewDevices_AfterCheck);
                    currNode.Parent.Checked = true;//选中父结点的时候,会触发选中事件,导致又重复选中子结点,所以要先注销选中事件,然后再注册
                    treeViewDevices.AfterCheck += new System.Windows.Forms.TreeViewEventHandler(this.treeViewDevices_AfterCheck);
                }
            }
            else//当前结点未选中
            {
                bool flag = false;
                TreeNodeCollection parentNodes = currNode.Parent.Nodes;
                foreach (TreeNode treenode in parentNodes)
                {
                    if (treenode.Checked)
                    {
                        flag = true;
                        break;
                    }
                }
                if (flag)//说明父结点的状态应该为选中状态
                {
                    if (currNode.Parent.Checked == false)
                    {
                        treeViewDevices.AfterCheck -= new System.Windows.Forms.TreeViewEventHandler(this.treeViewDevices_AfterCheck);
                        currNode.Parent.Checked = true;//选中父结点的时候,会触发选中事件,导致又重复选中子结点,所以要先注销选中事件,然后再注册
                        treeViewDevices.AfterCheck += new System.Windows.Forms.TreeViewEventHandler(this.treeViewDevices_AfterCheck);
                    }
                }
                else//无需选中父结点
                {
                    if (currNode.Parent.Checked == true)
                    {
                        currNode.Parent.Checked = false;
                    }
                }
            }
        }

TreeView的bug在这里有解决方法

http://social.msdn.microsoft.com/Forums/windows/en-US/9d717ce0-ec6b-4758-a357-6bb55591f956/possible-bug-in-net-treeview-treenode-checked-state-inconsistent?forum=winforms