关键代码：

        /// <summary>        ///同步父子节点勾选状态        ///说明        ///在AfterCheckNode事件中使用代码        ///eg:e.Node.SyncNodeCheckState(e.Node.CheckState);        /// </summary>        /// <param name="node">需要同步的节点</param>        /// <param name="check">节点当前勾选状态</param>        public static void SyncNodeCheckState(this TreeListNode node, CheckState check)        {            SyncNodeCheckState_Child(node, check);            SyncNodeCheckState_Parent(node, check);        }        private static void SyncNodeCheckState_Child(TreeListNode node, CheckState check)        {            if (node != null)            {                node.DownRecursiveNode(n => n.CheckState = check);            }        }        private static void SyncNodeCheckState_Parent(TreeListNode node, CheckState check)        {            if (node.ParentNode != null)            {                bool _cked = false;                CheckState _ckState;                foreach (TreeListNode cn in node.ParentNode.Nodes)                {                    _ckState = cn.CheckState;                    if (check != _ckState)                    {                        _cked = !_cked;                        break;                    }                }                node.ParentNode.CheckState = _cked ? CheckState.Indeterminate : check;                SyncNodeCheckState_Parent(node.ParentNode, check);            }        }

        /// <summary>        /// 向下递归TreeListNode节点        /// </summary>        /// <param name="node">需要向下递归的节点</param>        /// <param name="conditionHanlder">委托</param>        public static void DownRecursiveNode(this TreeListNode node, Action<TreeListNode> conditionHanlder)        {            foreach (TreeListNode _childNode in node.Nodes)            {                conditionHanlder(_childNode);                DownRecursiveNode(_childNode, conditionHanlder);            }        }

代码效果：