private void cargarcosto()
    {
        ServicioCom21.ServicioCom21 _consulta = new ServicioCom21.ServicioCom21();
        DataSet _costo = _consulta.Com21_consulta_costo();

        if (_costo.Tables[0].Rows.Count > 0)
        {
            prosi.Visible      = true;
            prono.Visible      = false;
            GvCosto.DataSource = _costo.Tables[0];
            GvCosto.DataBind();
        }
        else
        {
            prosi.Visible = false;
            prono.Visible = true;
        }
    }