Getting a sub category based on a category name

Question

How can I get a subcategory name based on a category name in a WordPress post?

For example, consider 'volume' is the parent category. It has child categories like section1, section2, section3, etc. Then, section2 has another child category like article1, article2, etc.

In other words, the tree structure looks like this:

• volume
  • section1
  • section2
    • article1
    • article2
  • section3

I want to get the section1, section2, section3 etc. names by 'volume', and I also want to get article1, article2 etc. by section2.

How can I do this?

Answer 1

If you want to get all the descendents for the volume category and its ID is lets say 5:

$categories = get_categories( array(
                'child_of' => 5
              ));
foreach($categories as $category) { 
   echo '<p>Category: <a href="' . get_category_link( $category->term_id ) . '" title="' . sprintf( __( "View all posts in %s" ), $category->name ) . '" ' . '>' . $category->name.'</a> </p> ';
   echo '<p> Description:'. $category->description . '</p>';
   echo '<p> Post Count: '. $category->count . '</p>';  
}