Custom cart item price based on user input in Woocommerce - php

Question

in our Woocommerce store we have some minimum price for any products . And in every product inner page there is two filed where customer can type width , height of the product . And then they can add this product to cart, then price is changed based on given width and height.
For example if the minimum price for a product is 50 . And customer add width =2, height=3 , then the price for this product is going to 50*2*3=300
So to arrange this we add this code to function.php
add_filter( 'woocommerce_add_cart_item', 'add_custom_cart_item_data', 10, 2 );
function add_custom_cart_item_data( $cart_item_data, $cart_item_key ) {
$result=$_POST['width']*$_POST['height']*$cart_item_data['data']->price;
$cart_item_data['new-price'] =$result;
$cart_item_data['data']->set_price($result);
return $cart_item_data;
}
So this is working correctly .
But the problem is once it is coming to checkout page then the product price is showing as 50 , but it is 300 actually.
so to overcome this i use the following code
add_filter( 'woocommerce_cart_item_subtotal', 'update_with_custom_details', 10, 3 );
function update_with_custom_details( $subtotal, $cart_item, $cart_item_key ) {
$subtotal =" £".$cart_item['line_total'];
return $subtotal;
}
now it is showing £300, but i know this code is wrong.
The code is wrong because when customer apply a 50% coupon code for this product then the discount is coming as 25 , Because it calculating based on 50*.5=25; But actually product new price is 300, so the discount should be 300*5=150;
So how i can update the product price in cart page, checkout page ,mini cart etc ?
Please help .
Please see this also
Woocommerce product custom price is not accepted by wocommerce coupon

Answer 1

Update 2: The correct way to do it need to be done in two steps:
We calculate the price on add to cart event hook and save it as custom cart item data.
We set that calculated price in woocommerce_before_calculate_totals hook
The code:
// Save custom field value in cart item as custom data
add_filter( 'woocommerce_add_cart_item_data', 'calculate_custom_cart_item_prices', 30, 3 );
function calculate_custom_cart_item_prices( $cart_item_data, $product_id, $variation_id ) {
if ( isset($_POST['width']) && isset($_POST['height']) ) {
// Get the correct Id to be used (compatible with product variations)
$the_id = $variation_id > 0 ? $variation_id : $product_id;
$product = wc_get_product( $the_id ); // Get the WC_Product object
$product_price = (float) $product->get_price(); // Get the product price
// Get the posted data
$width = (float) sanitize_text_field( $_POST['width'] );
$height = (float) sanitize_text_field( $_POST['height'] );
$new_price = $width * $height * $product_price; // Calculated price
$cart_item_data['calculated-price'] = $new_price; // Save this price as custom data
}
return $cart_item_data;
}
// Set custom calculated price in cart item price
add_action( 'woocommerce_before_calculate_totals', 'set_calculated_cart_item_price', 20, 1 );
function set_calculated_cart_item_price( $cart ) {
if ( is_admin() && ! defined( 'DOING_AJAX' ) )
return;
if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
return;
// Loop through cart items
foreach ( $cart->get_cart() as $cart_item ){
if( ! empty( $cart_item['calculated-price'] ) ){
// Set the calculated item price (if there is one)
$cart_item['data']->set_price( $cart_item['calculated-price'] );
}
}
}
Code goes in function.php file of your active child theme (or theme). Tested and works.
For testing purpose, I have used the following code that output 2 custom fields on single product pages:
// The hidden product custom field
add_action( 'woocommerce_before_add_to_cart_button', 'add_gift_wrap_field' );
function add_gift_wrap_field() {
global $product;
// The fake calculated price
?>
<div>
<label class="product-custom-text-label" for="servicetime"><?php _e( 'Custom text:', 'woocommerce'); ?><br>
<input type="text" id="user-width" name="width" value=""><br>
<input type="text" id="user-height" name="height" value="">
</label>
</div><br>
<?php
}