有新的信息有托盘提示

 using System;
using System.IO;
using System.Net;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Collections.Generic;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        private bool m_bFlag = true;       
        //根据Url地址得到网页的HTML源码
        private string GetWebContent(string Url)
        {
            string strResult = "";
            try
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
                //声明一个HttpWebRequest请求
                request.Timeout = 30000;
                //设置连接超时时间
                request.Headers.Set("Pragma", "no-cache");
                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                Stream streamReceive = response.GetResponseStream();
                Encoding encoding = Encoding.GetEncoding("gb2312");
                StreamReader streamReader = new StreamReader(streamReceive, encoding);
                strResult = streamReader.ReadToEnd();
                streamReader.Close();
            }
            catch
            {
                MessageBox.Show("出错");
            }
            return strResult;
        }
       
        public Form1()
        {
            InitializeComponent();
            this.notifyIcon1.Icon = new Icon("1.ico");
            this.SizeChanged += new System.EventHandler(this.Form1_SizeChanged);
            this.timer2.Enabled = true;
            this.timer2.Tick += new System.EventHandler(this.timer2_Tick);
        }
        private void Form1_SizeChanged(object sender, System.EventArgs e)
        {
            if (this.WindowState == FormWindowState.Minimized)
            {
                this.Hide();
            }
        }

        //关闭
        private void toolStripMenuItem4_Click(object sender, System.EventArgs e)
        {
            this.Close();
        }
        //显示
        private void toolStripMenuItem3_Click(object sender, EventArgs e)
        {
            if (this.WindowState == FormWindowState.Minimized)
            {
                this.Show();
                this.WindowState = FormWindowState.Normal;
                this.Activate();
                this.timer1.Stop();
                this.notifyIcon1.Icon = new Icon("1.ico");
            }
        }

        //抓
        private void timer2_Tick(object sender, System.EventArgs e)
        {
            //抓取数据
            string Url = "http://192.168.2.27:91/admin/Admin_User.asp";
            string strWebContent = GetWebContent(Url);
            FileStream fs = new FileStream(@"1.txt", FileMode.Open, FileAccess.Read);
            StreamReader sr = new StreamReader(fs);
            string strData = sr.ReadToEnd();
            sr.Close();
            fs.Close();
            if (strWebContent != strData)
            {
                this.webBrowser1.Refresh();
                this.timer1.Start();
                this.timer1.Tick += new EventHandler(this.timer1_Tick);
                StreamWriter sw = new StreamWriter("1.txt");
                sw.Write(strWebContent);
                sw.Close();
            }
        }
        //闪
        private void timer1_Tick(object sender, System.EventArgs e)
        {
            if (m_bFlag)
            {
                this.notifyIcon1.Icon = new Icon("2.ico");
                m_bFlag = false;
            }
            else
            {
                this.notifyIcon1.Icon = new Icon("1.ico");
                m_bFlag = true;
            }
        }
    }
}