How To bring the form at front, on double click of notifyIcon in system tray

Hi,
   In .net windows application, I have NofifyIcon, I want that, when  I will doubkleClick on this, it should bring the form to front.

My code snippets are

  private void myAppIcon_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            if (ShowChatWindowOnNotify == true && IsWindowMinimized == true)
            {
                // Show();
                this.Instance.Show();
                WindowState = FormWindowState.Maximized;     
                ShowChatWindowOnNotify = false;
                IsWindowMinimized = false;
            }
         
            this.Activate();
            this.BringToFront();
            this.Focus();
      }

Here it's opening the form, but not getting it to the front from the other open windows.
can anybody help me in this?

end of post

Hi can u look into my code,

  private void myAppIcon_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            if (ShowChatWindowOnNotify == true && IsWindowMinimized == true)
            {
                // Show();
                this.Instance.Show();
                this.Activate();
                WindowState = FormWindowState.Maximized;
                this.Focus();
               // this.BringToFront();
                SetForegroundWindow(this.Handle);
                ShowChatWindowOnNotify = false;
                IsWindowMinimized = false;
                this.TopMost = true;
            }
            else
            {
                this.Activate();               
                this.Focus();
//                this.BringToFront();
                SetForegroundWindow(this.Handle);
                this.TopMost = true;
            }

  [return: MarshalAs(UnmanagedType.Bool)]
        [DllImport("user32", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
        public static extern bool SetForegroundWindow(IntPtr hwnd);

  // Property to check and keep open only once instance of chat form.
            public Chat Instance
            {
                get
                {
                    if (Chat._instance != null)
                    {
                        Chat._instance.Close();

                    }
                    Chat._instance = new Chat();
                    Chat._instance.Activate();
                    Chat._instance.Focus();
                    Chat._instance.BringToFront();
                    return Chat._instance;
                }
            }

And on all new instances of your Chat class