我创建了代码片段，但没有看到任何变化。 检查此 链接到实时预览

<?php
// Calculates price based on selected booking start time and minimum order hours
add_action( 'woocommerce_before_calculate_totals', 'cwpai_booking_price_calculation', 10, 1 );
function cwpai_booking_price_calculation( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) ) {
        return;
    }
    
    foreach ( $cart->get_cart() as $cart_item ) {
        $product_id = $cart_item['product_id'];

        // Get start time and minimum order hours
        $start_time = strtotime($_POST['wc_bookings_field_start_date'][0] . ' ' . $_POST['wc_bookings_field_start_time'][0]);
        $minimum_hours = get_post_meta( $product_id, '_minimum_duration', true );

        // Check if start time and minimum order hours meet condition
        if ( date('H:i', $start_time) >= '22:00' && date('H:i', $start_time) <= '10:00' && $minimum_hours >= 6 ) {
            // Calculate maximum cost for 6 hours
            $max_cost = $cart_item['data']->get_price() * 6;

            // Get current cost based on duration
            $duration = WC_Bookings_Cart::calculate_booking_duration( $cart_item['booking'], true, true );
            $current_cost = $duration['cost'];

            // Update cost to maximum cost for 6 hours
            if ( $current_cost > $max_cost ) {
                $cart_item['data']->set_price( $max_cost );
            }
        }
    }
}

// Update post meta when product is saved
add_action( 'woocommerce_process_product_meta', 'cwpai_update_booking_meta' );
function cwpai_update_booking_meta( $post_id ) {
    // Only run for bookable products
    if ( get_post_meta( $post_id, '_wc_booking_type', true ) !== 'booking' ) {
        return;
    }
    
    // Get minimum order hours
    $minimum_hours = isset( $_POST['_minimum_duration'] ) ? absint( $_POST['_minimum_duration'] ) : 0;

    // Update post meta with new booking cost
    if ( $minimum_hours >= 6 ) {
        $max_cost = get_post_meta( $post_id, '_price', true ) * 6;
        update_post_meta( $post_id, '_new_booking_cost', $max_cost );
    } else {
        delete_post_meta( $post_id, '_new_booking_cost' );
    }
}

// Modify product costs to new booking cost
add_filter( 'woocommerce_product_get_price', 'cwpai_modify_product_costs', 10, 2 );
add_filter( 'woocommerce_product_get_regular_price', 'cwpai_modify_product_costs', 10, 2 );
function cwpai_modify_product_costs( $price, $product ) {
    $new_booking_cost = get_post_meta( $product->get_id(), '_new_booking_cost', true );

    if ( $new_booking_cost ) {
        $price = $new_booking_cost;
    }

    return $price;
}