Set product variation custom calculated price dynamically in WooCommerce - php

Question

I am trying to dynamically add to a products price when a user checks out based on what they have entered in the product page. The setting of the price is only working on a non variation product.
I need to be able to set the price on the variations of the products as well.
The code that I am using:
function add_cart_item_data( $cart_item_meta, $product_id, $variation_id ) {
$product = wc_get_product( $product_id );
$price = $product->get_price();
$letterCount = strlen($_POST['custom_name']);
$numberCount = strlen($_POST['custom_number']);
if($letterCount != '0') {
$letterPricing = 20 * $letterCount;
$numberPricing = 10 * $numberCount;
$additionalPrice = $letterPricing + $numberPricing;
$cart_item_meta['custom_price'] = $price + $additionalPrice;
}
return $cart_item_meta;
}
function calculate_cart_total( $cart_object ) {
if ( is_admin() && ! defined( 'DOING_AJAX' ) ) {
return;
}
foreach ( $cart_object->cart_contents as $key => $value ) {
if( isset( $value['custom_price'] ) ) {
$price = $value['custom_price'];
$value['data']->set_price( ( $price ) );
}
}
}

Answer 1

I have completely revisited your code:
// Set custom data as custom cart data in the cart item
add_filter( 'woocommerce_add_cart_item_data', 'add_custom_data_to_cart_object', 30, 3 );
function add_custom_data_to_cart_object( $cart_item_data, $product_id, $variation_id ) {
if( ! isset($_POST['custom_name']) || ! isset($_POST['custom_number']) )
return $cart_item_data; // Exit
if( $variation_id > 0)
$product = wc_get_product( $variation_id );
else
$product = wc_get_product( $product_id );
$price = $product->get_price();
// Get the data from the POST request and calculate new custom price
$custom_name = sanitize_text_field( $_POST['custom_name'] );
if( strlen( $custom_name ) > 0 )
$price += 20 * strlen( $custom_name );
$custom_number = sanitize_text_field( $_POST['custom_number'] );
if( strlen( $custom_number ) > 0 )
$price += 10 * strlen( $custom_number );
// Set new calculated price as custom cart item data
$cart_item_data['custom_data']['price'] = $price;
return $cart_item_data;
}
// Set the new calculated price of the cart item
add_action( 'woocommerce_before_calculate_totals', 'set_new_cart_item_price', 50, 1 );
function set_new_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_data']['price'] ) ) {
// Get the new calculated price
$new_price = (float) $cart_item['custom_data']['price'];
// Set the new calculated price
$cart_item['data']->set_price( $new_price );
}
}
}
This code goes on function.php file of your active child theme (or theme).
Tested and works as well with product variations.