写的一个监控端口获得数据的,但是每各一段时间就不监控了,请问该怎么搞``哪的问题哦``

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Threading;
using System.Net.Sockets;
using System.Net;
using System.IO;
using System.Security.Cryptography;
using System.Text.RegularExpressions;namespace JK
{
    public partial class Form1 : Form
    {
        private HttpServer server = new HttpServer();
        public Form1()
        {
            InitializeComponent();            server.Start();
            lblZhuangTai.Text = "状态：正在监控...";        }        private void btnTingZhi_Click(object sender, EventArgs e)
        {
            server.Stop();
            lblZhuangTai.Text = "状态：停止监控";
        }        private void btnKaiShiJianKong_Click(object sender, EventArgs e)
        {
            server.Start();
            lblZhuangTai.Text = "状态：正在监控...";
        }        public class HttpServer
        {
            TcpListener _listener = null;
            ManualResetEvent _waitEvent = null;
            Thread t;
            public void Start()
            {
                _waitEvent = new ManualResetEvent(false);
                //开始侦听所有IP的9887端口
                _listener = new TcpListener(IPAddress.Any, 9887);
                _listener.Start();                _waitEvent.Reset();                //开始处理客户端连接请求
                t = new Thread(new ThreadStart(ThreadDeamon));
                t.IsBackground = true;
                t.Start();
            }            private void ThreadDeamon()
            {
                while (!_waitEvent.WaitOne(1000, false))
                {
                    //如果有挂起的请求
                    if (_listener.Pending())
                    {
                        //接收一个请求
                        TcpClient client = _listener.AcceptTcpClient();
                        //得到客户端IP地址
                        string ip = ((IPEndPoint)client.Client.RemoteEndPoint).Address.ToString();
                        //Console.WriteLine(String.Format("来自： {0}", ip));
                        //获得数据
                        NetworkStream ns = client.GetStream();
                        MemoryStream ms = new MemoryStream();
                        byte[] buffer = new byte[1024];
                        int read = 0;                        while (ns.DataAvailable)
                        {
                            read = ns.Read(buffer, 0, buffer.Length);
                            if (read > 0)
                            {
                                ms.Write(buffer, 0, read); //如果网络流中有可用的数据那么就写如到内存留
                            }
                            else
                            {
                                break;
                            }
                        }                        //输出客户端请求的数据到控制台
                        byte[] data = ms.ToArray();
                        string recivedString = Encoding.UTF8.GetString(data);                        //Console.WriteLine();
                        //Console.WriteLine(recivedString);
                        //Console.WriteLine();                        //解析参数，即Http里的QueryString
                        ms.Seek(0, SeekOrigin.Begin);                        StreamReader sr = new StreamReader(ms);
                        string headerline = sr.ReadLine();                        sr.Close();                        //获取网址?号后面的字符传
                        int start = headerline.IndexOf("?") + 1;
                        int length = headerline.IndexOf("HTTP/1.1") - start;
                        string[] args = headerline.Substring(start, length).Trim().Split(new char[] { '&' });                        Dictionary<string, string> queryString = new Dictionary<string, string>();
                        foreach (string arg in args)
                        {
                            string[] p = arg.Split(new char[] { '*' });
                            if (p.Length == 2 && !queryString.ContainsKey(p[0]))
                                queryString.Add(p[0], p[1]);
                        }
                        if (!queryString.ContainsKey("signstr"))
                            return;
                        string strRet = "false";
                        //根据参数执行不同的任务。
                        //省略                        //执行任务完成后，返回执行结果。注意：需要遵守Html协议                        string ret = string.Format(RESPONSE, DateTime.Now.ToUniversalTime(), strRet.Length, strRet);
                        byte[] sendData = Encoding.UTF8.GetBytes(ret);
                        ns.Write(sendData, 0, sendData.Length);
                        //ns.Close();
                        client.Close();
                        //Console.WriteLine(String.Format("client {0} disconnected.", ip));
                    }
                }
            }            const string RESPONSE = @"HTTP/1.1 200 OK
Date: {0}
Server: IYOND-SERVER
Content-Type: text/html; charset=UTF-8
Content-Length: {1}
Connection: close{2}
";            public void Stop()
            {
                _waitEvent.Set();
                _listener.Stop();
                t.Interrupt();
                //System.Diagnostics.Process.GetCurrentProcess().Kill();
            }        }
    }
}帮我看看有没有什么问题``谢谢``