[C#] ping指定ip寫入log檔

最近做了一個小程式，每隔10秒用來ping某個指定IP確認網路穩定性，並將結果寫入txt做紀錄。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net.NetworkInformation;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace testNetwork
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        System.IO.StreamWriter file;
        bool run = false;
        private void button1_Click(object sender, EventArgs e)
        {
            file =new System.IO.StreamWriter("log.txt");
            run = true;
            backgroundWorker1.RunWorkerAsync();
           
        }

        private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {
            while (run)
            {
                PingIt();
                Thread.Sleep(10000);
            }
        
    
        }

        private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            label1.Text = message;
        }
        string message;
        public void PingIt()
        {
           
            Ping p = new Ping();
            var ip = textBox1.Text;
            string time=DateTime.Now.ToString("h:mm:ss tt");
            PingReply r = p.Send(ip);
            if (r.Status == IPStatus.Success)
                message = string.Format("{1}  IP:{0} pint test ok！", ip, time);
            else
                message = string.Format("{1}  IP:{0} pint test failed！", ip, time);

            backgroundWorker1.ReportProgress(0);

            try
            {
                file.WriteLine(message);
            }
            catch
            {

            }
           
        }

        private void Form1_Load(object sender, EventArgs e)
        {


        }

        private void button2_Click(object sender, EventArgs e)
        {
            run = false;
            file.Flush();
            file.Close();
            
        }

    }
}