在产品编辑页面添加自定义复选框以保存设置（是和否）

Question

在 从 WooCommerce 中计算的额外费用中排除某些产品回答我之前的问题之后，我对之前的代码中的数组进行了一些更改。
然后，我在产品编辑页面添加了一个复选框：如果它处于活动状态（选中），则不会计算该产品的税费。如果它处于非活动状态（默认情况下未选中），则会计算税费。

1。修改函数以包含排除的数组：

// +9% tax add-fee on paypal
add_action( 'woocommerce_cart_calculate_fees', 'add_checkout_fee_for_gateway', 10, 1 );
function add_checkout_fee_for_gateway( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) ) 
        return;

    // Retrieve excluded product IDs from post meta
    $excluded_product_ids = get_option('excluded_product_ids', array());
    
    // Only on checkout page and for specific payment method ID
    if ( is_checkout() && ! is_wc_endpoint_url() 
    && WC()->session->get('chosen_payment_method') === 'paypal' ) {
        $percentage_rate      = 0.09; // Defined percentage rate
        $custom_subtotal      = 0; // Initializing
        
        // Loop through cart items
        foreach( $cart->get_cart() as $item ) {
            // Calculate items subtotal from non excluded products
            if( ! in_array($item['product_id'], $excluded_product_ids) ) {
                $custom_subtotal += (float) $item['line_subtotal'];
            }
        }

        if ( $custom_subtotal > 0 ) {
            $cart->add_fee( __('9% value added tax'), ($custom_subtotal * $percentage_rate), true, '' );
        }
    }
}

2。添加复选框到产品编辑页面：

// Add checkbox to product edit page
add_action('woocommerce_product_options_general_product_data', 'add_custom_product_field');
function add_custom_product_field() {
    global $post;

    // Checkbox field
    woocommerce_wp_checkbox(
        array(
            'id'            => 'exclude_from_tax',
            'wrapper_class' => 'show_if_simple',
            'label'         => __('Exclude from Tax Calculation'),
            'description'   => __('Check this box to exclude this product from tax calculation.'),
            'value'         => get_post_meta($post->ID, 'exclude_from_tax', true) ? 'yes' : 'no',
        )
    );
}

// Save checkbox value
add_action('woocommerce_process_product_meta', 'save_custom_product_field');
function save_custom_product_field($post_id) {
    // Checkbox field
    $checkbox = isset($_POST['exclude_from_tax']) ? 'yes' : 'no';
    update_post_meta($post_id, 'exclude_from_tax', $checkbox);
}

或者这个：（组合版本！（也许更好））

add_action('woocommerce_cart_calculate_fees', 'add_checkout_fee_and_product_field', 10, 1);
function add_checkout_fee_and_product_field($cart) {
    if (is_admin() && !defined('DOING_AJAX'))
        return;

    // Retrieve excluded product IDs from post meta
    $excluded_product_ids = get_option('excluded_product_ids', array());

    // Add checkbox to product edit page
    add_action('woocommerce_product_options_general_product_data', 'add_custom_product_field');
    function add_custom_product_field() {
        global $post;

        // Checkbox field
        woocommerce_wp_checkbox(
            array(
                'id' => 'exclude_from_tax',
                'wrapper_class' => 'show_if_simple',
                'label' => __('Exclude from Tax Calculation'),
                'description' => __('Check this box to exclude this product from tax calculation.'),
                'value' => get_post_meta($post->ID, 'exclude_from_tax', true) ? 'yes' : 'no',
            )
        );
    }

    // Save checkbox value
    add_action('woocommerce_process_product_meta', 'save_custom_product_field');
    function save_custom_product_field($post_id) {
        // Checkbox field
        $checkbox = isset($_POST['exclude_from_tax']) ? 'yes' : 'no';
        update_post_meta($post_id, 'exclude_from_tax', $checkbox);
    }

    // Only on checkout page and for specific payment method ID
    if (is_checkout() && !is_wc_endpoint_url() && WC()->session->get('chosen_payment_method') === 'paypal') {
        $percentage_rate = 0.09; // Defined percentage rate
        $custom_subtotal = 0; // Initializing

        // Loop through cart items
        foreach ($cart->get_cart() as $item) {
            // Calculate items subtotal from non excluded products
            if (!in_array($item['product_id'], $excluded_product_ids)) {
                $custom_subtotal += (float)$item['line_subtotal'];
            }
        }

        if ($custom_subtotal > 0) {
            $cart->add_fee(__('9% value added tax'), ($custom_subtotal * $percentage_rate), true, '');
        }
    }
}

现在不知道我的方法和代码是否正确？实际上是否与 WordPress 和 WooCommerce 的插件、主题或核心不兼容？或者它不会在新的和未来的版本中创建？不会损坏数据库吗？是否可以用更干净、更少的代码以更好、更安全、更简单的方式做到这一点？

Answer 1

您的代码中存在一些错误...请尝试以下修改后的代码版本：

// Percentage tax fee for paypal payment
add_action( 'woocommerce_cart_calculate_fees', 'add_checkout_fee_for_gateway', 10, 1 );
function add_checkout_fee_for_gateway( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) ) 
        return;
    
    // Only on checkout page and for specific payment method ID
    if ( is_checkout() && ! is_wc_endpoint_url() 
    && WC()->session->get('chosen_payment_method') === 'paypal' ) {

        // Retrieve excluded product IDs from options
        $percentage_rate      = 0.09; // Defined percentage rate
        $custom_subtotal      = 0; // Initializing
        
        // Loop through cart items
        foreach( $cart->get_cart() as $item ) {
            $product = wc_get_product( $item['product_id'] );
            // Calculate items subtotal from non excluded products
            if( $product->get_meta('_tax_fee_excluded') !== 'yes' ) {
                $custom_subtotal += (float) $item['line_subtotal'];
            }
        }

        if ( $custom_subtotal > 0 ) {
            $cart->add_fee( __('9% value added tax'), ($custom_subtotal * $percentage_rate), true, '' );
        }
    }
}

// Add a checkbox to product edit page
add_action('woocommerce_product_options_general_product_data', 'add_admin_product_custom_field');
function add_admin_product_custom_field() {

    // Checkbox field
    woocommerce_wp_checkbox( array(
        'id'            => '_tax_fee_excluded',
        'wrapper_class' => 'show_if_simple',
        'label'         => __('Exclude from Tax Calculation'),
        'description'   => __('Check this box to exclude this product from tax calculation.')
    ) );
}

// Save checkbox value from product edit page
add_action('woocommerce_admin_process_product_object', 'save_admin_product_custom_field_value');
function save_admin_product_custom_field_value( $product ) {
    $product->update_meta_data('_tax_fee_excluded', isset($_POST['_tax_fee_excluded']) ? 'yes' : 'no');
}

代码位于子主题的functions.php 文件中（或插件中）。已测试并有效。