How to add a product to the cart when adding another product?

Question

1C-Bitrix

Hello colleagues!
After update 18.1.3, Add2BasketByProductID does not seem to work.
For certain products, you need to add another previously known product to the cart.
On the OnBeforeBasketAdd event, I use the Add2BasketByProductID method to add a product.

AddEventHandler("sale", "OnBeforeBasketAdd", Array("CSaleHandlers","OnBeforeBasketAddHandler") );

class CSaleHandlers{
   function OnBeforeBasketAddHandler(&$arFields) {
      $arID = array(896,897,898,899,900,901,902,903,904,906,1457,1458);
      if( in_array($arFields["PRODUCT_ID"], $arID) ){
         $pos = Add2BasketByProductID( 1027, 2, array(), array() );
         AddMessage2Log('$pos = '.print_r($pos, true),'');
      }
   }
}

As a result, I get the item position code in the cart in $pos, that is, the method worked, there is no error. But there is no item in the cart.
If the product with PRODUCT_ID = 1027 is already in the cart, then the method successfully adds the specified quantity of 2 pcs to it.

Answer 1

Evgeny Zhukov on the forum helped to solve this issue by advising to use the \Bitrix\Catalog\Product\Basket::addProduct method (for public components) and \Bitrix\Catalog\Product\Basket::addProductToBasket (for arbitrary, including administrative scripts)."

Answer 2

After function Add2BasketByProductID try to add

if ($ex = $APPLICATION->GetException()){
     \Bitrix\Main\Diag\Debug::dumpToFile($ex->GetString());
}

You can try adding an item to your cart like this:

$product = array(
    'PRODUCT_ID' => $productId,
    'QUANTITY' => $quantity
);
/*@var $basketResult Bitrix\Main\Result*/
$basketResult = Catalog\Product\Basket::addProduct($product);
if (!$basketResult->isSuccess()) {
    \Bitrix\Main\Diag\Debug::dumpToFile(implode('; ', $basketResult->getErrorMessages()));
}

logs from dumpToFile can be viewed in /__bx_log.log