How to do I get the unc path value from text box

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Net;
using System.Diagnostics;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Net.Configuration;
using System.Runtime.InteropServices;

namespace ListNetworkComputers
{
    /// <summary>
    /// A simply test form that creates a new NetworkBrowser
    /// object, and displays a list of the network computers
    /// found by the NetworkBrowser
    /// </summary>
    public partial class frmMain : Form
    {
        /// <summary>
        /// Constructor
        /// </summary>
        public frmMain()
        {
            InitializeComponent();
        }


        private void frmMain_Load(object sender, EventArgs e)
        {

            
        }

        private void button1_Click(object sender, EventArgs e)
        {
           
        }

        private void Scanbtn_Click(object sender, EventArgs e)
        {
            Process netUtility = new Process();

            netUtility.StartInfo.FileName = "net.exe";

            netUtility.StartInfo.CreateNoWindow = true;

            netUtility.StartInfo.Arguments = "view";

            netUtility.StartInfo.RedirectStandardOutput = true;

            netUtility.StartInfo.UseShellExecute = false;

            netUtility.StartInfo.RedirectStandardError = true;

            netUtility.Start();



            StreamReader streamReader = new StreamReader(netUtility.StandardOutput.BaseStream, netUtility.StandardOutput.CurrentEncoding);



            string line = "";

            while ((line = streamReader.ReadLine()) != null)
            {
                if (line.StartsWith("\\"))
                {


                    string pcname = line.Substring(2).Substring(0, line.Substring(2).IndexOf(" ")).ToUpper();
                    string myIP = Convert.ToString(System.Net.Dns.GetHostByName(line.Substring(2).Substring(0, line.Substring(2).IndexOf(" ")).ToUpper()).AddressList[0].ToString());
                    string fullname = "PC Name : " + pcname + " IP Address : " + myIP;
                    listBox1.Items.Add(pcname);
                    listBox2.Items.Add(myIP);
                }
            }

            streamReader.Close();
            netUtility.WaitForExit(1000);


        }
       
        private void button1_Click_1(object sender, EventArgs e)
        {
            Application.Exit();
        }

        private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            
        }

        private void listBox2_SelectedIndexChanged(object sender, EventArgs e)
        {

            string ipaddress = listBox2.GetItemText(listBox2.SelectedItem);
            System.Net.IPAddress ip = System.Net.IPAddress.Parse(ipaddress);
            
            IPtxt.Text = listBox2.SelectedItem.ToString();

           // string text = listBox2.GetItemText(listBox2.SelectedItem);
            
          //  label1.Text = listBox2.SelectedItem.ToString();

        }

        private void cTextBox1_TextChanged(object sender, EventArgs e)
        {

        }
    }
}