使用产品自定义字段值覆盖woocommerce购物车商品价格

Question

In woocommerce I am using Advanced Custom Fields and trying to get a custom field value in each product as price instead of the default product price. this custom field is called 'custom_price'.

How can I change this hard coded value to use that instead?

Here is my code:

 add_action( 'woocommerce_before_calculate_totals', 'add_custom_price' 
 );

 function add_custom_price( $cart_object ) {
     $custom_price = 10; 
     foreach ( $cart_object->cart_contents as $key => $value ) {
         $value['data']->set_price($custom_price);
     }
 }

Answer 1

Update 3: Here is the complete solution with all custom fields and the cart item price change.

You will need to add some jQuery code to make your product price calculation, display calculated price on product page and set this calculated price on a hidden field.

Once product will be added to cart, the code will catch the calculated price and will set it in the corresponding cart item…

The code:

// The product custom field - Frontend
add_action( 'woocommerce_before_add_to_cart_button', 'custom_discount_price_product_field' );
function custom_discount_price_product_field() {
    global $product;

    $curs = get_woocommerce_currency_symbol(); // Currency symbol

    // Get the discounted value (from product backend)
    $discount = (float) get_post_meta( $product->get_id(), '_price_discount', true );

    // jQuery will get the discount here for calculations
    echo '<input type="hidden" name="price_discount" value="'.$discount.'">';

    echo '<div>';

    woocommerce_form_field( 'select_price', array(
        'type'          => 'select',
        'class'         => array('my-field-class form-row-wide'),
        'label'         => __('Discount'),
        'options'     => array(
            ''      => __( 'Select your discount', 'woocommerce' ),
            '5'     => $curs . '5',
            '10'    => $curs . '10',
            '15'    => $curs . '15',
            '20'    => $curs . '20',
        ),
    ), '' );

    // This field will be used to send the calculated price
    // jQuery will set the calculated price on this field
    echo '<input type="hidden" name="custom_price" value="52">'; // 52 is a fake value for testing purpose

    echo '</div><br>';

    // BELOW your jquery code to calculate price and update "custom_price" hidden field
    ?>
    <script type="text/javascript">
    jQuery( function($){
        // Here
    });
    </script>
    <?php
}

// Add a custom field to product in backend
add_action( 'woocommerce_product_options_pricing', 'add_field_product_options_pricing' );
function add_field_product_options_pricing() {
    global $post;

    echo '<div class="options_group">';

    woocommerce_wp_text_input( array(
        'id'            => '_price_discount',
        'label'         => __('Discount price', 'woocommerce') . ' (%)',
        'placeholder'   => __('Set the Discount price…', 'woocommerce'),
        'description'   => __('Enter the custom value here.', 'woocommerce'),
        'desc_tip'      => 'true',
    ));

    echo '</div>';
}

// Save product custom field to database when submitted in Backend
add_action( 'woocommerce_process_product_meta', 'save_product_options_custom_fields', 30, 1 );
function save_product_options_custom_fields( $post_id ){
    // Saving custom field value
    if( isset( $_POST['_price_discount'] ) ){
        update_post_meta( $post_id, '_price_discount', sanitize_text_field( $_POST['_price_discount'] ) );
    }
}

// Add custom calculated price conditionally as custom data to cart items
add_filter( 'woocommerce_add_cart_item_data', 'add_custom_price_to_cart_item_data', 20, 2 );
function add_custom_price_to_cart_item_data( $cart_item_data, $product_id ){
    if( ! isset($_POST['custom_price']) )
        return $cart_item_data;

    $cart_item_data['custom_price'] = (float) sanitize_text_field( $_POST['custom_price'] );
    $cart_item_data['unique_key'] = md5( microtime() . rand() ); // Make each item unique

    return $cart_item_data;
}

// Set conditionally a custom item price
add_action('woocommerce_before_calculate_totals', 'set_cutom_cart_item_price', 20, 1);
function set_cutom_cart_item_price( $cart ) {
    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
        return;

    foreach (  $cart->get_cart() as $cart_item ) {
        if ( isset( $cart_item['custom_price'] ) )
            $cart_item['data']->set_price( $cart_item['custom_price'] );
    }
}

Code goes in function.php file of your active child theme (or active theme). Tested and works (but you will need to make your own calculations with jquery)