Hello reader's today we discussed about "How to get child of Category".

In Wordpress, if we create a category and their sub category and we want to call category and their sub-category. In Programming language we called it Parent Child relation. The below code define how parent child relation work. We can create a custom post type called gallery and taxonomy name is gallery-category. $images store all the featured image of the category. "$term_id = $term->term_id" with this we can find the current category id.

    <?php

    $term =  get_term_by( 'slug', get_query_var( 'term' ), get_query_var( 'taxonomy' ) );

    $term_id = $term->term_id;
    function category_has_children() {
        global $wpdb;   
        $term = get_queried_object();
        $category_children_check = $wpdb->get_results(" SELECT * FROM wp_term_taxonomy WHERE parent = '$term->term_id' ");
        if ($category_children_check) {
            return true;
        } else {
           return false;
        }
    }

   if(!category_has_children()){
    $my = get_posts(array(
        'post_type' => 'gallery',
        'posts_per_page'  => -1,
        'order'     => 'ASC', 
        'tax_query' => array(
            array(
            'taxonomy' => 'gallery-category',
            'field' => 'term_id',
            'terms' => $term_id)
        ))
    );
    foreach ($my as $post) {
        $full_img = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'full');
        $images = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'post-thumb');
?>
    <div class="col-sm-4 gallerypic">
        <a class="fancybox" href="<?php echo $full_img[0];?>" data-fancybox-group="gallery" title="<?php the_title(); ?>">
            <img src="<?php echo $images[0];?>" alt="" />
            <h4><?php echo $post->post_title; ?></h4>
        </a>
    </div>

<?php
        }
    }
?>