private void exercício4ToolStripMenuItem_Click(object sender, EventArgs e)
{
frmExercicio4 frm4 = new frmExercicio4();
frm4.MdiParent = this;
frm4.WindowState = FormWindowState.Minimized;
frm4.Show();
}
private void exercicio4ToolStripMenuItem_Click(object sender, EventArgs e)
{
Form fc = Application.OpenForms["frmExercicio4"];
if (fc != null)
{
fc.Close();
}
frmExercicio4 frm = new frmExercicio4();
frm.MdiParent = this;
frm.WindowState = FormWindowState.Maximized;
frm.Show();
}