private void txtape_TextChanged(object sender, EventArgs e)
 {
     if (radioButton1.Checked && (txtnom.TextLength >= 1 || txtape.TextLength >= 1))
     {
         Base_de_datos busc = new Base_de_datos();
         busc.BuscarEE(txtnom.Text.ToUpper(), txtape.Text.ToUpper());
         dataGridView1.DataSource = busc.Mostrar_Resultados();
     }
     else
     {
         dataGridView1.DataSource = null;
     }
 }
 private void txtId_TextChanged(object sender, EventArgs e)
 {
     if (radioButton2.Checked && txtId.TextLength == 13)
     {
         Base_de_datos busc = new Base_de_datos();
         busc.BuscarEE(txtId.Text);
         dataGridView1.DataSource = busc.Mostrar_Resultados();
     }
     else
     {
         dataGridView1.DataSource = null;
     }
 }