private void cmb_emp_SelectedIndexChanged(object sender, EventArgs e) { try { SistemaUsuarioDatos ss = new SistemaUsuarioDatos(); DataTable dtjc2 = new DataTable(); dtjc2 = ss.SeleccionaColaborador(Convert.ToString(cmb_emp.SelectedValue)); if (dtjc2.Rows.Count != 0) { cmb_colab.DataSource = dtjc2; cmb_colab.DisplayMember = "nombre"; cmb_colab.ValueMember = "id_empleados_pk"; } else { cmb_colab.SelectedIndex = -1; } } catch (Exception ex) { MessageBox.Show(ex.Message); } }