Shortcode to show the (child)categories a post belongs to

I think i have found the php code for showing the childcategories inside a post. This code works inside the loop.

<?php
$sep = '';
foreach((get_the_category()) as $childcat) {
if (cat_is_ancestor_of(27, $childcat)) {
echo $sep.'',$childcat->cat_name,'';
$sep = ' / ';
}}
?>

How to turn it into a shortcode [region] that can be used inside a post?

function region($atts) {
$sep = '';
foreach((get_the_category()) as $childcat) {
if (cat_is_ancestor_of(27, $childcat)) {
echo $sep.'',$childcat->cat_name,'';
$sep = ' / ';
}}}

add_shortcode('region', 'region');

seems to work… but it places the childcategories above the post and not inside the text.

Almost there… just need that little bit of help 😉

Hello siobhyb,

This code does integrate a list of child categories

In this case [region]
Change 35 into the parent category
Change

$sep = ', ';

into something else in order to have a different separator. For instance

$sep = ' / ';

Good luck with your project!

/**
 * Shortcode function to show child categories
 * [region]
 */

function region($atts) {
	$sep = '';
	$output = '';
	foreach((get_the_category()) as $childcat) {
		if (cat_is_ancestor_of(35, $childcat)) {

$output .= $sep . $childcat->cat_name;
$sep = ', ';
			}
		}
	return $output;
}
add_shortcode('region', 'region');

All thanks for this code goes to alchymyth who was so kind to help me with this code.