private void PcbDisponivel_Click(object sender, EventArgs e)
 {
     if (Application.OpenForms.OfType <FrmModo>().Count() == 0)
     {
         FrmModo tela = new FrmModo(funcionario.Login);
         tela.Show();
     }
 }
 private void ModosDoGerenteToolStripMenuItem_Click(object sender, EventArgs e)
 {
     if (Application.OpenForms.OfType <FrmModo>().Count() == 0)
     {
         FrmModo tela = new FrmModo(txtLogin.Text);
         tela.Show();
     }
 }