How Do I Make The Tree View List View Explorer

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;
using System.IO;
using System.Collections;

namespace Assignment1b
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            DriveInfo[] drives = DriveInfo.GetDrives();
            for (int i = 0; i <= drives.Length - 1; i++)
            {
                comboBox1.Items.Add(drives[i].Name);
                comboBox1.SelectedIndex = -1;
            }
        }

        private void gobtn_Click(object sender, EventArgs e)
        {
            ShowTreeViewItems(pathtb.Text);
            ShowDirectoryItems(pathtb.Text);
        }

        private void listView1_ItemActivate(object sender, EventArgs e)
        {
            pathtb.Text = pathtb.Text + listView1.SelectedItems[0].Text + "\\";
            ShowTreeViewItems(pathtb.Text);
            ShowDirectoryItems(pathtb.Text);
        }
        private void ShowTreeViewItems(string Path)
        {
            try
            {
                DirectoryInfo CurrDir = new DirectoryInfo(Path);
                DirectoryInfo[] SubDirs = CurrDir.GetDirectories();
                FileInfo[] Files = CurrDir.GetFiles();

                treeView1.Nodes.Clear();

                TreeNode parentNode = new TreeNode();
                parentNode.Text = Path;
                parentNode.ForeColor = Color.Black;
                parentNode.BackColor = Color.White;
                parentNode.ImageIndex = 2;
                parentNode.SelectedImageIndex = 2;
                treeView1.Nodes.Add(parentNode);

                foreach (DirectoryInfo dir in SubDirs)
                {
                    TreeNode childNode = new TreeNode();
                    childNode.Text = dir.Name;
                    childNode.ForeColor = Color.Black;
                    childNode.BackColor = Color.White;
                    childNode.ImageIndex = 2;
                    childNode.SelectedImageIndex = 2;
                    parentNode.Nodes.Add(childNode);
                    ////////////////////////////////////////////////////////
                    //TreeNode currentNode = new TreeNode();
                    //currentNode.Text = childNode.FullPath;
                    //currentNode.ForeColor = Color.Black;
                    //currentNode.BackColor = Color.White;
                    //currentNode.ImageIndex = 2;
                    //currentNode.SelectedImageIndex = 2;
                    //childNode.Nodes.Add(currentNode);

                }

                foreach (FileInfo file in Files)
                {
                    TreeNode childNode = new TreeNode();
                    childNode.Text = file.Name;
                    childNode.ForeColor = Color.Black;
                    childNode.BackColor = Color.White;
                    childNode.ImageIndex = 0;
                    childNode.SelectedImageIndex = 0;
                    parentNode.Nodes.Add(childNode);
                    ////////////////////////////////////////////////////
                    //TreeNode currentNode = new TreeNode();
                    //currentNode.Text = file.Name; ;
                    //currentNode.ForeColor = Color.Black;
                    //currentNode.BackColor = Color.White;
                    //currentNode.ImageIndex = 0;
                    //currentNode.SelectedImageIndex = 0;
                    //childNode.Nodes.Add(currentNode);
                }
                ShowDirectoryItems(Path);
            }
            catch (Exception e)
            {
                MessageBox.Show(e.Message.ToString());
            }
        }

        private void ShowDirectoryItems(string Path)
        {
            DirectoryInfo CurrDir = new DirectoryInfo(Path);
            DirectoryInfo[] SubDirs = CurrDir.GetDirectories();
            FileInfo[] Files = CurrDir.GetFiles();

            DateTime dateModified;

            listView1.Items.Clear();

            listView1.BeginUpdate();

            foreach (DirectoryInfo dir in SubDirs)
            {
                ListViewItem item = new ListViewItem();
                item.Text = dir.Name;
                item.ImageIndex = 1;

                listView1.Items.Add(item);
            }

            foreach (FileInfo file in Files)
            {
                ListViewItem item = new ListViewItem();
                item.Text = file.Name;
                item.ImageIndex = 0;

                dateModified = File.GetLastWriteTime(file.FullName.ToString());
                item.SubItems.Add(dateModified.ToString());

                item.SubItems.Add((file.Length / 1024) + " KB");
                listView1.Items.Add(item);
            }

            listView1.EndUpdate();

        }

        private void treeView1_NodeMouseDoubleClick(object sender, TreeNodeMouseClickEventArgs e)
        {
            pathtb.Text = e.Node.FullPath.ToString();
            ShowTreeViewItems(e.Node.FullPath.ToString());
        }

        private void treeView1_AfterSelect(object sender, TreeViewEventArgs e)
        {
        }

        private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            treeView1.Nodes.Clear();
            DirectoryInfo CurrDir = new DirectoryInfo(comboBox1.SelectedItem.ToString());
            DirectoryInfo[] SubDir = CurrDir.GetDirectories();
            FileInfo[] Files = CurrDir.GetFiles();

            try
            {
                foreach (DirectoryInfo dir in SubDir)
                {
                    TreeNode node = treeView1.Nodes.Add(dir.Name);
                    node.Nodes.Add("");
                }
                foreach (FileInfo file in Files)
                {
                    if (file.Extension.ToLower() == ".txt")
                    {
                        TreeNode node = treeView1.Nodes.Add(file.Name);
                    }
                }
                
                
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void treeView1_BeforeExpand(object sender, TreeViewCancelEventArgs e)
        {
            try
            {
                TreeNode currentNode = e.Node;
                DirectoryInfo FolderPath = new DirectoryInfo(comboBox1.SelectedItem + currentNode.FullPath);
                DirectoryInfo[] Folder = FolderPath.GetDirectories();
                FileInfo[] Files = FolderPath.GetFiles();

                foreach (DirectoryInfo dir in Folder)
                {
                    TreeNode node = currentNode.Nodes.Add(dir.Name);
                    node.Nodes.Add(" ");
                }

                foreach (FileInfo file in Files)
                {
                    if ((file.Extension).ToLower() == ".txt")
                    {
                        TreeNode newNode = currentNode.Nodes.Add(file.Name);
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e)
        {
            comboBox1.Items.Add(e.Node.Text);
        }

        
    }
}