How to write function for getting subcategories of particular category?

Question

function productDescription()
{
    $_helper = Mage::helper('catalog/category');
    $category = Mage::getModel('catalog/category')->load($categoryId);
    $_categories = $category->getChildrenCategories() 
    print_r($_categories);
    $array = json_encode($_categories);
    file_put_contents("product_node.json", $array);
}

Answer 1

You can try this:

public function getCategories()
{
    $categoryId = 2;
    $categoryTree = Mage::getResourceModel('catalog/category')->getCategories($categoryId);

    $array = array();
    foreach ($categoryTree as $category) {
        $array[$category->getPathId()] = $category->getName();
        $array = array_merge($array, $this->_getChildren($category));
    }
    var_dump($array);
}

public function _getChildren($category, $array = array())
{
    if ($category->getChildrenCount()) {
        foreach ($category->getChildren() as $child) {
            $array[$child->getPathId()] = $child->getName();
            $this->_getChildren($child, $array);
        }
    }
    return $array;
}

Output looks like:

array(
    '1/2/5' => 'Men',
    '1/2/5/14' => 'New Arrivals',
    '1/2/5/15' => 'Shirts',
    ...
);

Answer 2

Try like this

$children = Mage::getModel('catalog/category')->getCategories(10);
foreach ($children as $category) {
    echo $category->getName();
}

Answer 3

Please use the folowing code :

<?php $_helper = Mage::helper('catalog/category') ?>
<?php $categoryId = 3;?>
<?php $category = Mage::getModel('catalog/category')->load($categoryId) ?>
<?php $_categories = $category->getChildrenCategories() ?>

<?php if (count($_categories) > 0): ?>
    <ul>
        <?php foreach($_categories as $_category): ?>
            <li>
                <a href="<?php echo $_helper->getCategoryUrl($_category) ?>"><?php echo $_category->getName() ?></a>
                <?php $_category = Mage::getModel('catalog/category')->load($_category->getId()) ?>
                <?php if($_category->hasChildren()):?>
                <?php $_subcategories = $_category->getChildrenCategories() ?>
                    <ul>
                        <?php foreach($_subcategories as $_subcategory): ?>
                            <li>
                                <a href="<?php echo $_helper->getCategoryUrl($_subcategory) ?>"><?php echo $_subcategory->getName() ?></a>
                                <?php $_category2 = Mage::getModel('catalog/category')->load($_subcategory->getId()) ?>
                                <?php if($_category2->hasChildren()):?>
                                <?php $_subcategories2 = $_category2->getChildrenCategories() ?>
                                    <ul>
                                        <?php foreach($_subcategories2 as $_subcategory2): ?>
                                            <li>
                                                <a href="<?php echo $_helper->getCategoryUrl($_subcategory2) ?>"><?php echo $_subcategory2->getName() ?></a>
                                            </li>
                                        <?php endforeach; ?>
                                    </ul>
                                <?php endif; ?>

                            </li>
                        <?php endforeach; ?>
                    </ul>
                <?php endif; ?>
            </li>
        <?php endforeach; ?>
    </ul>
<?php endif; ?>

Source from How get all subcategories of specific category?

Answer 4

Try the below code:-

<?php
    //gets all sub categories of parent category 'Brands'
     $cate_id = Mage::getModel('catalog/layer')->getCurrentCategory()->getId();

    $cats = Mage::getModel('catalog/category')->load($cate_id)->getChildren();
    $catIds = explode(',',$cats);
    //print_r ($catIds);
    $categories = array();
    foreach($catIds as $catId) {
        $category = Mage::getModel('catalog/category')->load($catId); 
        $categories[$category->getName()] = array(
            'url' => $category->getUrl(),
            'img' => $category->getImageUrl(),
            'name'=>$category->getName(),
            'thumb'=>$category->getThumbnail(),
            'id'=>$category->getId()
        );
    }
    ksort($categories, SORT_STRING);
?>
<?php if (Mage::getModel('catalog/category')->load($cate_id)->getChildren()):?>
    <ul class="subs_cats row">
        <?php //print_r($catIds); ?>
        <?php foreach($categories as $name => $data): ?>

            <li class="sub_cate span6" style="text-align:center;font-size: 15px;font-weight:bold;">
                <div class="cate_img img-responsive">
                <?php if($data['thumb'] ==''): ?>
                <a href="<?php echo $data['url'];?>" title="<?php echo $data['name'];?>" alt="<?php echo $data['name'];?>"><img class="cat-ge" src="<?php echo $this->getSkinUrl('images/no_preview.png') ?>"></img></a>
                    <?php else: ?>
                       <a href="<?php echo $data['url'];?>" title="<?php echo $data['name'];?>" alt="<?php echo $data['name'];?>"><img class="cat-image" src="<?php echo Mage::getBaseUrl('media').'catalog/category/'.$data['thumb']; ?>" ></img></a>
                    <?php  endif; ?>
                </div>
                <div class="main_cate">

                <?php //echo $data['name']; ?>

                <?php if(strlen($data['name']) >=22):?>
                <a href="<?php echo $data['url'];?>" title="<?php echo $data['name'];?>" alt="<?php echo $data['name'];?>"><?php echo substr($data['name'],0, 22).' ...'; ?></a>
                <?php else:?>
                <a href="<?php echo $data['url'];?>" title="<?php echo $data['name'];?>" alt="<?php echo $data['name'];?>"><?php echo $data['name'];?></a>
                <?php endif;?>

                </div>
            </li>
        <?php endforeach; ?>
    </ul>
    <?php else:?>
        <p class="note-msg"><?php echo $this->__('There are no Subcategories for this category.');?></p>
<?php endif;?>