private void exercício4ToolStripMenuItem_Click(object sender, EventArgs e)
{
frmExercício4 frm4 = new frmExercício4();
frm4.MdiParent = this;
frm4.WindowState = FormWindowState.Maximized;
frm4.Show();
}
private void exercício4ToolStripMenuItem_Click(object sender, EventArgs e)
{
Form fc = Application.OpenForms["frmExercício4"];
if (fc != null)
{
fc.Close();
}
frmExercício4 objFrm4 = new frmExercício4();
objFrm4.MdiParent = this;
objFrm4.WindowState = FormWindowState.Maximized;
objFrm4.Show();
}