求救！！！QQ闪烁功能，可是我最大或正常状态，在最小还不停的闪烁

Question

namespace LAN
{
    public partial class Form1 : Form
    {
        private DialogResult result;
        private TcpListener tcpLister = new TcpListener(9988);
        System.Threading.ThreadStart listenPort;
        System.Threading.Thread lister;
        public Thread th;
        public Thread tj;
        Thread l;
        private System.Drawing.Icon Icon1, Icon2;
        private string message;
        private bool Nfirst = false;
        public Form1()
        {
            InitializeComponent();
            Icon1 = notif.Icon;
            Icon2 = notify1.Icon;
            this.MaximizeBox = false;
            listenPort += new ThreadStart(this.listen);
            lister = new Thread(listenPort);
        }        private void Form1_Load(object sender, EventArgs e)
        {            IpClass ic = new IpClass();
            this.label3.Text = ic.name();
            this.label4.Text = ic.ipc();
            this.label5.Text = ic.data();
            this.textBox1.AppendText("正在监听...\r\n");
            lister.Name = "监听本地端口";
            lister.Start();
        }
        private void listen()
        {
            try
            {
                tcpLister.Start();
                while (true)
                {
                    //接受挂起的请求
                    Socket s = tcpLister.AcceptSocket();
                    Byte[] stream = new Byte[80];
                    int i = s.Receive(stream);
                    message= System.Text.Encoding.UTF8.GetString(stream);
                    this.textBox1.AppendText(message);
                    if (WindowState == FormWindowState.Minimized)
                    {
                        
                        th = new Thread(new ThreadStart(So));
                        th.Start();
                    }
                    FlashWindow(Handle, true);
                }
            }
            catch (System.Security.SecurityException)
            {
                MessageBox.Show("防火墙安全错误！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
            }
            catch (System.Exception)
            {
                //this.textBox1.AppendText("已停止监听！");
            }
        }        private void abortLister(object sender, System.ComponentModel.CancelEventArgs e)
        {
            this.tcpLister.Stop();
        }
        //发送消息
        [DllImport("user32.dll")]
        public static extern bool FlashWindow(
            IntPtr hWnd,     // handle to window
            bool bInvert   // flash status
            );
        private void Send()
        {
            try
            {
                Nfirst = true;
                string msg = this.label3.Text + " (" + System.DateTime.Now.ToString() + ")\r\n" + this.textBox2.Text + "\r\n";          
                TcpClient client = new TcpClient(this.listBox1.SelectedItem.ToString(),9988);
                NetworkStream sendStream = client.GetStream();
                StreamWriter writer = new StreamWriter(sendStream);
                writer.Write(msg); 
                writer.Flush();
                sendStream.Close();
                client.Close();
                this.textBox1.AppendText(msg);
                this.textBox2.Clear();
            }
            catch (System.Exception)
            {
                this.textBox1.AppendText("目标计算机拒绝连接请求！\r\n");
            }
        }
 private void button1_Click(object sender, EventArgs e)
        {
            if (this.textBox2.Text == "")
            {
                try
                {
                    MessageBox.Show("不能发送空信息！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                }
                catch
                {
                    MessageBox.Show("不能发送空信息！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                }
            }
            else
            {
                this.Send();
            }
        }
  private void notif_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            this.Visible = true;
            this.notif.Visible = false;
            this.notif.Icon = Icon1;
            this.WindowState = FormWindowState.Normal;
            
        }
  private void Form1_Resize(object sender, EventArgs e)
        {
            if (this.WindowState ==FormWindowState.Minimized)
            {
                this.WindowState = FormWindowState.Minimized;
                this.Visible = false;
                this.notif.Visible = true;
            }
        }
请问怎么改啊