Show related posts' categories in WordPress - php

Question

I am trying to also display the category of a related post, below one article.
I am using Newsmag theme.
The code that builds my related posts is this:
class td_module {
var $post;
var $title_attribute;
var $title;
var $href;
var $td_review; //review meta
var $category;
//constructor
function __construct($post) {
//this filter is used by td_unique_posts.php - to add unique posts to the array for the datasource
apply_filters("td_wp_boost_new_module", $post);
$this->post = $post;
$this->title = get_the_title($post->ID);
$this->title_attribute = esc_attr(strip_tags($this->title));
$this->href = esc_url(get_permalink($post->ID));
$this->category = '';
if (has_post_thumbnail($this->post->ID)) {
$this->post_has_thumb = true;
} else {
$this->post_has_thumb = false;
}
//get the review metadata
$this->td_review = get_post_meta($this->post->ID, 'td_review', true);
}
and the part that displays the related articles is this:
$buffy .= '<div class="td-module-thumb">';
if (current_user_can('edit_posts')) {
$buffy .= '<a class="td-admin-edit" href="' . get_edit_post_link($this->post->ID) . '">edit</a>';
}
$buffy .='<a href="' . $this->href . '" rel="bookmark" title="' . $this->title_attribute . '">';
$buffy .= '<img width="' . $td_temp_image_url[1] . '" height="' . $td_temp_image_url[2] . '" itemprop="image" class="entry-thumb" src="' . $td_temp_image_url[0] . '" ' . $attachment_alt . $attachment_title . '/>';
$buffy .= '<span class="td-module-thumb-category">'.$this->category.'</span>';
....................................
$this->category was added by me. I am trying to get the data from wp_terms table and display the categories of each of the related posts.
I am new to WordPress(actually, this is the first time I touch WordPress code).
Thank you

Answer 1

This should work with your existing code:
$buffy .= '<div class="td-module-thumb">';
$related_category = get_the_category($this->post->ID);
if (current_user_can('edit_posts')) {
$buffy .= '<a class="td-admin-edit" href="' . get_edit_post_link($this->post->ID) . '">edit</a>';
}
$buffy .='<a href="' . $this->href . '" rel="bookmark" title="' . $this->title_attribute . '">';
$buffy .= '<img width="' . $td_temp_image_url[1] . '" height="' . $td_temp_image_url[2] . '" itemprop="image" class="entry-thumb" src="' . $td_temp_image_url[0] . '" ' . $attachment_alt . $attachment_title . '/>';
$buffy .= '<span class="td-module-thumb-category">'.$related_category[0]->cat_name.'</span>';
Or if you need the category to be a link use:
$buffy .= '<div class="td-module-thumb">';
$related_category = get_the_category($this->post->ID);
if (current_user_can('edit_posts')) {
$buffy .= '<a class="td-admin-edit" href="' . get_edit_post_link($this->post->ID) . '">edit</a>';
}
$buffy .='<a href="' . $this->href . '" rel="bookmark" title="' . $this->title_attribute . '">';
$buffy .= '<img width="' . $td_temp_image_url[1] . '" height="' . $td_temp_image_url[2] . '" itemprop="image" class="entry-thumb" src="' . $td_temp_image_url[0] . '" ' . $attachment_alt . $attachment_title . '/>';
$buffy .= '<span class="td-module-thumb-category">'.$related_category[0]->cat_name.'</span>';
You will probably want to move $related_category = get_the_category($this->post->ID); to where you have $this->category = ''; in your first pasted code segment