using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

namespace TreeView的使用

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            MessageBox.Show(treeView1.SelectedNode.Text);

        }

        private void button2_Click(object sender, EventArgs e)

        {

            //Nodes是第一级节点的集合，在第一级节点添加，即根节点

            //treeView1.Nodes.Add()

            //在第一个根节点的下一级添加

            //treeView1.Nodes[0].Nodes.Add("aaa");

            //根据用户选择添加信息

            if(treeView1.SelectedNode != null)

            {

                treeView1.SelectedNode.Nodes.Add(textBox1.Text);

            }

            else

            {

                treeView1.Nodes.Add(textBox1.Text);

            }

        }

        private void Form1_Load(object sender, EventArgs e)

        {

            //展开所有节点

            treeView1.ExpandAll();

        }

        private void button3_Click(object sender, EventArgs e)

        {

            treeView1.CollapseAll();

        }

        private void button4_Click(object sender, EventArgs e)

        {

            treeView1.ExpandAll();

        }

        private void button5_Click(object sender, EventArgs e)

        {

            treeView1.SelectedNode.Collapse();

        }

        private void button6_Click(object sender, EventArgs e)

        {

            //当前节点的的下一级节点

            treeView1.SelectedNode.Expand();

            //当前节点的所有节点

            //treeView1.SelectedNode.ExpandAll();

        }

        private void button7_Click(object sender, EventArgs e)

        {

            treeView1.SelectedNode.Remove();

        }

        private void button8_Click(object sender, EventArgs e)

        {

            treeView1.SelectedNode.Text = textBox2.Text;

        }

        private void button9_Click(object sender, EventArgs e)

        {

            string str = "选中的节点：\n";

            foreach(TreeNode tn in treeView1.Nodes[0].Nodes[0].Nodes)

            {

                if(tn.Checked)

                    str += tn.Text+"\n";

            }

            MessageBox.Show(str);

        }

        private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)

        {

        }

        private void treeView1_AfterCheck(object sender, TreeViewEventArgs e)

        {

            foreach(TreeNode tn in e.Node.Nodes)

            {

                tn.Checked = e.Node.Checked;

            }

        }

    }

}