Check if category is child of another

Question

I know how to check what the parent category id is, but what I am trying to do is find out if the current category is a child of a specific category, up to 2 levels deep.

For example: if user is browsing child2 in category1/child1/child2, detecting if child2 is a child of category1

Is there a function that handles this?

Or

should I create a helper with an iterator that climbs up the tree?

Answer 1

You can pull the path of the current category:

$path = $category->getPath();

The path contains the location in the category tree of the current category separated by a /. You can do the following to iterate through each category in the path to search for the one you are interested in as being a parent:

$path = explode('/', $path);
array_pop($path); // throw away the current category
array_pop($path); // throw away the parent category
$gparent = array_pop($path); // this is the category you are interested in

If you want to search any category in the tree for the particular parent you could just use a foreach loop:

$path = explode('/', $path);
array_pop($path); // throw away the current category
array_shift($path); // throw away the highest level category which is always 1 (and you don't even see in the tree)
foreach ($path as $p):
    if ($p == $gparent):
        // do something here
    endif;
endforeach;