private void cargaCombo() { cnx = new SqlConnection(cdn); cmd = new SqlCommand(); cmd.Connection = cnx; ch = new Conceptos.Core.ConceptosHelper(); ch.Command = cmd; Conceptos.Core.Conceptos concepto = new Conceptos.Core.Conceptos(); concepto.idempresa = GLOBALES.IDEMPRESA; if (rbtnDeducciones.Checked) concepto.tipoconcepto = "D"; if (rbtnPercepcion.Checked) concepto.tipoconcepto = "P"; List<Conceptos.Core.Conceptos> lstConceptos = new List<Conceptos.Core.Conceptos>(); try { cnx.Open(); lstConceptos = ch.obtenerConceptosDeducciones(concepto, _periodo); cnx.Close(); cnx.Dispose(); } catch (Exception error) { MessageBox.Show("Error: \r\n \r\n" + error.Message, "Error"); } cmbConcepto.DataSource = lstConceptos; cmbConcepto.DisplayMember = "concepto"; cmbConcepto.ValueMember = "id"; }