如何在Woocommerce产品变体可变属性下拉列表中添加库存状态

    add_filter( 'woocommerce_dropdown_variation_attribute_options_HTML', 'show_stock_status_in_dropdown', 10, 2);

    function show_stock_status_in_dropdown( $html, $args ) {

        $options = $args['options']; 

        $product = $args['product']; 

        $attribute = $args['attribute']; 

        $name = $args['name'] ? $args['name'] : 'attribute_' . sanitize_title( $attribute ); 

        $id = $args['id'] ? $args['id'] : sanitize_title( $attribute ); 

        $class = $args['class']; 

        $show_option_none = $args['show_option_none'] ? true : false; 

        $show_option_none_text = $args['show_option_none'] ? $args['show_option_none'] : __( 'Choose an option', 'woocommerce' ); 

      // Get all product variations

        $variations = $product->get_available_variations();

        if ( empty( $options ) && ! empty( $product ) && ! empty( $attribute ) ) { 

            $attributes = $product->get_variation_attributes(); 

            $options = $attributes[ $attribute ]; 

        } 

        $html = '<select id="' . esc_attr( $id ) . '" class="' . esc_attr( $class ) . '" name="' . esc_attr( $name ) . '" data-attribute_name="attribute_' . esc_attr( sanitize_title( $attribute ) ) . '" data-show_option_none="' . ( $show_option_none ? 'yes' : 'no' ) . '">'; 

        $html .= '<option value="">' . esc_html( $show_option_none_text ) . '</option>'; 

        if ( ! empty( $options ) ) { 

            if ( $product && taxonomy_exists( $attribute ) ) { 

              // Get terms if this is a taxonomy - ordered. We need the names too. 

              $terms = wc_get_product_terms( $product->get_id(), $attribute, array( 'fields' => 'all' ) ); 

              foreach ( $terms as $term ) { 

                    if ( in_array( $term->slug, $options ) ) { 

                        $html .= '<option value="' . esc_attr( $term->slug ) . '" ' . selected( sanitize_title( $args['selected'] ), $term->slug, false ) . '>' . esc_html( apply_filters( 'woocommerce_variation_option_name', $term->name ) ) . '</option>'; 

                    } 

                }

            } else {

                foreach ( $options as $option ) {

                        foreach ($variations as $variation) {

                            if($variation['attributes'][$name] == $option) {

                                $stock = $variation['is_in_stock'];

                            }

                        }       

                    if( $stock == 1) {

                        $stock_content = ' - (In Stock)';

                    } else {

                        $stock_content = ' - (Out of Stock)';

                    }

                     // This handles < 2.4.0 bw compatibility where text attributes were not sanitized. 

                    $selected = sanitize_title( $args['selected'] ) === $args['selected'] ? selected( $args['selected'], sanitize_title( $option ), false ) : selected( $args['selected'], $option, false ); 

                    $html .= '<option value="' . esc_attr( $option ) . '" ' . $selected . '>' . esc_html( $option  .  $stock_content ) . '</option>'; 

                }

            } 

        } 

        $html .= '</select>'; 

        return $html;

    }