private void btnAceptar_Click(object sender, EventArgs e)
        {
            cnx = new SqlConnection();
            cnx.ConnectionString = cdn;
            cmd = new SqlCommand();
            cmd.Connection = cnx;

            Conceptos.Core.ConceptosHelper ch = new Conceptos.Core.ConceptosHelper();
            ch.Command = cmd;

            try
            {
                cnx.Open();
                ch.actualizaConceptoTrabajador(_idEmpleado, GLOBALES.IDEMPRESA, int.Parse(cmbPeriodo.SelectedValue.ToString()));
                cnx.Close();
                cnx.Dispose();
            }
            catch (Exception)
            {
                MessageBox.Show("Error: Al actualizar los conceptos.", "Error");
                cnx.Dispose();
            }
        }