调试易

        private void GetTreeViewNode(TreeNode node1)
        {
            if (node1.Nodes != null)
            {
                foreach (TreeNode node2 in node1.Nodes)
                {
                    GetTreeViewNode(node2);
                }
            }
            else
            {
                if (node1.Checked)//选中的时候就。。
                {
                    //do something
                }
            }
        }

AfterCheck事件             private void treeView1_AfterCheck(object sender, TreeViewEventArgs e)
        {
            SetNodeCheckState((TreeNode)e.Node);
}  private void SetNodeCheckState(TreeNode parentNode)
        {
            foreach (TreeNode node in parentNode.Nodes)
            {
                if (parentNode.Checked == true)
                {
                    //node.Checked = true;
                    Console.WriteLine(node.Name);//输出选中的树节点，包括子节点。
                }
                //else
                   // node.Checked = false;// 此处如果选中父节点，同时选中子节点可去掉注释。
                if(node.Nodes.Count>0)
                 SetNodeCheckState(node);
            }
        }

        private void SetNodeCheckState(TreeNode parentNode)
        {
            if (parentNode.Nodes.Count > 1)
            {
                foreach (TreeNode node in parentNode.Nodes)
                {
                    if (parentNode.Checked == true)
                    {
                        node.Checked = true;
                        Console.WriteLine(node.Text);
                    }
                    else
                        node.Checked = false;
                    if (node.Nodes.Count > 0)
                        SetNodeCheckState(node);
                }
            }
            else
            {
                Console.WriteLine(parentNode.Text);
            }
        } 方法修改下，这样就可以显示没有子节点的信息。

void saa(TreeNode tn)
        {
            if (tn.Checked && tn.Tag!=null)
            {
                int id = Convert.ToInt32(tn.Tag);
                //MessageBox.Show(id.ToString());
                txt.Text += id.ToString() + ",";
            }
            if (tn.Nodes.Count>0)
            {
                foreach (TreeNode tn1 in tn.Nodes)
                {
                    saa(tn1);
                }
            }
        }只能获取第一个，第二个后都不能