Opción en el desplegable de ordenador por número de referencia (SKU)

// Para ordenador por numero de referencia (Código de Beka Rice https://www.skyverge.com/ )

/**
 * Adds the ability to sort products in the shop based on the SKU
 * Can be combined with tips here to display the SKU on the shop page: https://www.skyverge.com/blog/add-information-to-woocommerce-shop-page/
 */

function sv_add_sku_sorting( $args ) {

    $orderby_value = isset( $_GET['orderby'] ) ? wc_clean( $_GET['orderby'] ) : apply_filters( 'woocommerce_default_catalog_orderby', get_option( 'woocommerce_default_catalog_orderby' ) );

    if ( 'sku' == $orderby_value ) {
        $args['orderby'] = 'meta_value';
            $args['order'] = 'asc';
            // ^ lists SKUs alphabetically 0-9, a-z; change to desc for reverse alphabetical
        $args['meta_key'] = '_sku';
    }

    return $args;
}
add_filter( 'woocommerce_get_catalog_ordering_args', 'sv_add_sku_sorting' );


function sv_sku_sorting_orderby( $sortby ) {
    $sortby['sku'] = 'Sort by SKU';
    // Change text above as desired; this shows in the sorting dropdown
    return $sortby;
}
add_filter( 'woocommerce_catalog_orderby', 'sv_sku_sorting_orderby' );
add_filter( 'woocommerce_default_catalog_orderby_options', 'sv_sku_sorting_orderby' );