How to get root category using store id in magento 2 block file?

Question

How to get root category using store id. we get store id using $storeId = $this->getStoreId(); We use below code for get root category using store id; but we get wrong.

$rootCat = $this->_storeManager->getStore($storeId)->getRootCategoryId();

Any one help us for solve this.

Answer 1

You can use \Magento\Store\Model\StoreManagerInterface class to get store default root category Id.

<?php
class Test
{
    /**
     * @var \Magento\Store\Model\StoreManagerInterface
     */
    protected $storeManagerInterface;

    public function __construct(\Magento\Store\Model\StoreManagerInterface $StoreManagerInterface)
    {
         $this->storeManagerInterface = $StoreManagerInterface;
    }



    public function getRootCategoryId()
    {
        $store = 1;
        return $this->storeManagerInterface->getStore($store)->getRootCategoryId();
    }

}

Answer 2

I think something like this

namespace MyCompany\MyModule\Block;

class MyModel extends \Magento\Framework\View\Element\Template
{
    protected $_storeManager;    

    public function __construct(
        \Magento\Backend\Block\Template\Context $context,        
        \Magento\Store\Model\StoreManagerInterface $storeManager,        
        array $data = []
    )
    {        
        $this->_storeManager = $storeManager;        
        parent::__construct($context, $data);
    }

    /**
     * Get store identifier
     *
     * @return  int
     */
    public function getStoreId()
    {
        return $this->_storeManager->getStore()->getId();
    }

    /**
     * Get root category id for current store
     *
     * @return  int
     */

    public function getRootCategoryId()
    {
        return $this->storeManagerInterface->getStore($this->getStoreId())->getRootCategoryId();
        // or return $this->_storeManager->getStore()->getRootCategoryId();
    }
}

So in your block template phtml you will use

$block->getRootCategoryId();