Check whether a product is in the wishlist or not

Question

I\'m working on a Magento theme, and I need to build a function that can check to see whether or not a product has been added to the user\'s wishlist.

Magento has a

Answer 1

Since @alexadr.parhomenk s' solution causes undesired results, here's a smaller method that does the trick:

/**
 * Check customers wishlist on identity product.
 * @param int $productId
 * @return bool
 */
public function isInWishlist($productId)
{
    $ids = Mage::registry('wishlist_ids');
    if (!$ids) {
        $productCollection = Mage::helper('wishlist')->getWishlistItemCollection();
        $ids = $productCollection->getColumnValues('product_id');
        Mage::register('wishlist_ids', $ids);
    }
    return in_array($productId, $ids);
}