Добавление дополнительных полей можно сделать очень простым способом:
function jk_add_custom_sku() {
$args_1 = array(
'label' => __( 'Custom SKU', 'woocommerce' ),
'placeholder' => __( 'Enter custom SKU here', 'woocommerce' ),
'id' => 'jk_sku',
'desc_tip' => true,
'description' => __( 'This SKU is for internal use only.', 'woocommerce' ),
);
woocommerce_wp_text_input( $args_1 );
// Extra field
$args_2 = array(
'label' => __( 'Nominal codes', 'woocommerce' ),
'placeholder' => __( 'Enter nominal codes here', 'woocommerce' ),
'id' => '_nominal_codes',
'desc_tip' => true,
'description' => __( 'This is for nominal codes.', 'woocommerce' ),
);
woocommerce_wp_text_input( $args_2 );
}
add_action( 'woocommerce_product_options_sku', 'jk_add_custom_sku' );
// Save
function jk_save_custom_meta( $product ){
if( isset($_POST['jk_sku']) ) {
$product->update_meta_data( 'jk_sku', sanitize_text_field( $_POST['jk_sku'] ) );
}
// Extra field
if( isset($_POST['_nominal_codes']) ) {
$product->update_meta_data( '_nominal_codes', sanitize_text_field( $_POST['_nominal_codes'] ) );
}
}
add_action( 'woocommerce_admin_process_product_object', 'jk_save_custom_meta', 10, 1 );