如何通过从下拉产品变量中选择数量来更改购物车中的数量字段

Question

我在下面显示此代码，在商店页面上显示变量产品的变化下拉列表，但是当我选择一个选项（例如，示例5本书的数量）时，购物车显示book-5，而数量只有1个订单，则代码对待下拉菜单中的选项数量为颜色或大小... 有什么帮助吗?? !!

add_filter( 'woocommerce_loop_add_to_cart_link', 'woo_display_variation_dropdown_on_shop_page' );

 function woo_display_variation_dropdown_on_shop_page() {

    global $product;
    if( $product->is_type( 'variable' )) {

    $attribute_keys = array_keys( $product->get_variation_attributes() );
    ?>

    <form class="variations_form cart" method="post" enctype='multipart/form-data' data-product_id="<?php echo absint( $product->id ); ?>" data-product_variations="<?php echo htmlspecialchars( json_encode( $product->get_available_variations() ) ) ?>">
        <?php do_action( 'woocommerce_before_variations_form' ); ?>

        <?php if ( empty( $product->get_available_variations() ) && false !== $product->get_available_variations() ) : ?>
            <p class="stock out-of-stock"><?php _e( 'This product is currently out of stock and unavailable.', 'woocommerce' ); ?></p>
        <?php else : ?>
            <table class="variations" cellspacing="0">
                <tbody>
                    <?php foreach ( $product->get_variation_attributes() as $attribute_name => $options ) : ?>
                        <tr>
                            <td class="label"><label for="<?php echo sanitize_title( $attribute_name ); ?>"><?php echo wc_attribute_label( $attribute_name ); ?></label></td>
                            <td class="value">
                                <?php
                                    $selected = isset( $_REQUEST[ 'attribute_' . sanitize_title( $attribute_name ) ] ) ? wc_clean( urldecode( $_REQUEST[ 'attribute_' . sanitize_title( $attribute_name ) ] ) ) : $product->get_variation_default_attribute( $attribute_name );
                                    wc_dropdown_variation_attribute_options( array( 'options' => $options, 'attribute' => $attribute_name, 'product' => $product, 'selected' => $selected ) );
                                    echo end( $attribute_keys ) === $attribute_name ? apply_filters( 'woocommerce_reset_variations_link', '<a class="reset_variations" href="#">' . __( 'Clear', 'woocommerce' ) . '</a>' ) : '';
                                ?>
                            </td>
                        </tr>
                    <?php endforeach;?>
                </tbody>
            </table>

            <?php do_action( 'woocommerce_before_add_to_cart_button' ); ?>

            <div class="single_variation_wrap">
                <?php
                    /**
                     * woocommerce_before_single_variation Hook.
                     */
                    do_action( 'woocommerce_before_single_variation' );

                    /**
                     * woocommerce_single_variation hook. Used to output the cart button and placeholder for variation data.
                     * @since 2.4.0
                     * @hooked woocommerce_single_variation - 10 Empty div for variation data.
                     * @hooked woocommerce_single_variation_add_to_cart_button - 20 Qty and cart button.
                     */
                    do_action( 'woocommerce_single_variation' );

                    /**
                     * woocommerce_after_single_variation Hook.
                     */
                    do_action( 'woocommerce_after_single_variation' );
                ?>
            </div>

            <?php do_action( 'woocommerce_after_add_to_cart_button' ); ?>
        <?php endif; ?>

        <?php do_action( 'woocommerce_after_variations_form' ); ?>
    </form>

    <?php } else {

    echo sprintf( '<a rel="nofollow" href="%s" data-quantity="%s" data-product_id="%s" data-product_sku="%s" class="%s">%s</a>',
            esc_url( $product->add_to_cart_url() ),
            esc_attr( isset( $quantity ) ? $quantity : 1 ),
            esc_attr( $product->id ),
            esc_attr( $product->get_sku() ),
            esc_attr( isset( $class ) ? $class : 'button' ),
            esc_html( $product->add_to_cart_text() )
        );

    }

}