WordPress: Add custom text to posts matching a tag

The example below shows how to add text to the bottom of posts, based on specific conditions.

To get the right value for “custom_text”, you likely just want to add a paragraph tag, but you can copy existing HTML from your site to get a good example.

add_filter('the_content', 'custom_category_text');

function custom_category_text($content){
  global $post;
  $custom_text =
    '

Some example text...

'; $found = false; $re = "/\btag\b/i"; $posttags = get_the_tags(); if ($posttags) { foreach($posttags as $tag) { if ($found || preg_match($re, $tag->name)) { $found = true; } continue; } } if($found) { $content = $content . $custom_text; } return $content; }

If you want to look for specific words in the post slug, you can also add this:

  $slug = $post->post_name;
  if (preg_match($re, $slug)) {
    $found = true;
  }