Select sub-categories of a specific category of a product in Magento 1.9

Question

I am trying to write code for generating Google shopping feed in Magento 1.

I want to get categories assigned to a product which are subcategories of a specific category (Designers).

How do I do this?

I want to populate this in the brand tag in the XML and we do not have any manufacturers but store them in categories with a parent category called 'Designers'

Answer 1

You can manage to work by following code:

$designer_cat_id = 'YOUR DESIGNER CATEGORY ID';
$brands = array();
$categoryIds = $product->getCategoryIds();
if ($categoryIds)
{
    $categoryCollection = Mage::getModel('catalog/category')->getCollection();
    $categoryCollection->addAttributeToFilter('parent_id',['eq'=>$designer_cat_id]);
    $categoryCollection->addIdFilter($categoryIds);
    $categoryCollection->addNameToResult();
    if ($categoryCollection->getSize() > 0)
    {
        foreach ($categoryCollection as $cat)
        {
            $cat_name = $cat->getName();
            $url = $cat->getUrl();
            // Write your code for xml node creation
        }
    }
}

This code is not tested. This is basically an idea.