<?php
//functions.php
// add custom values to the shopping cart object
add_filter('woocommerce_add_cart_item_data', 'qpd_add_cart_item_data');
qpd_add_cart_item_data function($cart_item_data)
{
$cart_item_data['_quantity_per_day'] = 1;
return $cart_item_data;
}
//cart.php
// change the value of a variable quantity_per_day when you change input
?>
<td class="product-quantity"
data-title="<?php esc_attr_e('Quantity per day', 'woocommerce'); ?>">
<?php
$session_quantity_per_day = WC()->session->get('_quantity_per_day');
if (empty(filter_input(INPUT_POST, "quantity_per_day"))) {
$cart_item['_quantity_per_day'] = $session_quantity_per_day;
} else {
$cart_item['_quantity_per_day'] = filter_input(INPUT_POST, "quantity_per_day");
WC()->session->set('_quantity_per_day', $cart_item['_quantity_per_day']);;
}
echo '<div class="quantity">';
echo '<label class="screen-reader-text" for="quantity_per_day"></label>';
echo '<input type="number" class="input-text qty text quantity_per_day" name="quantity_per_day" value="' . $cart_item['_quantity_per_day'] . '">';
echo '</div>';
?>
</td>
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