private void button1_Click(object sender, EventArgs e)
{
int check;
if (radioButton1.Checked == true)
{
check = 1;
}
else
{
check = 0;
}
op.IngresarFactura(txtref.Text, txtid.Text, check, float.Parse(txtmonto.Text), cbcai.Text, cbmed.Text, Elegir_Examen.cod, Elegir_Examen.precio);
Menu men = new Menu();
men.Show();
this.Hide();
}