这一段是登录与主界面之间的关系,这样登录界面可以Close();
 frmLogin login = new frmLogin();
                    login.ShowDialog();
                    if (login.login_success)
                        Application.Run(new frmMain());这一段是最小化到系统托盘的
 private void frmLogin_SizeChanged(object sender, EventArgs e)
        {
            if (this.WindowState == FormWindowState.Minimized)
            {
                this.Hide();
                this.notifyIcon1.Visible = true;
            }
        }        private void notifyIcon1_MouseClick(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
                if (this.WindowState == FormWindowState.Minimized)
                {
                    this.ShowDialog();
                    this.WindowState = FormWindowState.Normal;
                }
                else
                {
                    this.WindowState = FormWindowState.Minimized;
                }
        }
但不知道为什么最小化后就关闭了,我看了下进程,进程关闭了;有没有高手知道怎么回事?怎么弄!!