private void SaveAsToolStripMenuItem_Click(object sender, EventArgs e)
{
Numerosp childForm = new Numerosp();
childForm.MdiParent = this;
childForm.Text = "Ventana " + childFormNumber++;
childForm.Show();
}
private void button4_Click(object sender, EventArgs e)
{
Numerosp frm1 = new Numerosp();
frm1.Show();
}