private void restaToolStripMenuItem_Click(object sender, EventArgs e)
{
FrmOperaciones frmop = new FrmOperaciones();
frmop.MdiParent = this;
frmop.BtnSuma.Enabled = false;
frmop.Show();
}
private void sumaToolStripMenuItem_Click(object sender, EventArgs e)
{
FrmOperaciones frmop = new FrmOperaciones();
frmop.MdiParent = this;
frmop.BtnResta.Enabled = false;
frmop.BtnMultiplicar.Enabled = false;
frmop.BtnDiv.Enabled = false;
frmop.Show();
}