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 TreeTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            TreeNode treeNode = new TreeNode(textBox1.Text, 2, 2);
            treeView1.Nodes.Add(treeNode);
            treeView1.Select();
        }

        private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)
        {

        }

        private void button2_Click(object sender, EventArgs e)
        {
            TreeNode selectdnode = treeView1.SelectedNode;
            if(selectdnode!=null)
            {
                TreeNode chnode = new TreeNode(textBox2.Text, 2, 2);
                selectdnode.Nodes.Add(chnode);
                selectdnode.Expand();
                treeView1.Select();
            }
            else
            {
                MessageBox.Show("請(qǐng)選擇需要添加子節(jié)點(diǎn)");
            }
        }

        private void button3_Click(object sender, EventArgs e)
        {
            TreeNode selectnode = treeView1.SelectedNode;
            TreeNode parentnode = selectnode.Parent; 
            if(parentnode == null)
            {
                treeView1.Nodes.Remove(selectnode);
            }
            else
            {
                parentnode.Nodes.Remove(selectnode);
            }
            treeView1.Select();
        }

        private void button4_Click(object sender, EventArgs e)
        {
            treeView1.Nodes.Clear();
        }

        private void button5_Click(object sender, EventArgs e)
        {
            this.textBox1.Clear();
            this.textBox2.Clear();
        }
    }
}