Add META Tags to WordPress Head

The reason that WordPress is so developer-friendly is their awesome hook system.  Depending on a post category (or seemingly anything else), you can modify the contents of the page, the theme templates, and everything else.  WordPress is amazing.

One recent use case I had was wanting to modify the <meta name="robots" content="{index? follow?}"> tag based on the post's category:  if the post is in category A, use noindex,nofollow, otherwise use index,follow.  After all not every post is a reflection of the overall site content.

Completing the task was easy using the WordPress hook system, specifically the wp_head hook:

// Worker function - echo tags to be added to the header
function dont_follow_some_posts() {
  global $IMPORTANT_CATEGORIES, $post;

  if(isset($post) && is_single($post) && in_category($IMPORTANT_CATEGORIES['sponsored'], $post->id)) {
    echo '';
  }
  else {
    echo '';
  }
}

// Hook into "wp_head" to add meta tags
add_filter('wp_head', 'dont_follow_some_posts');

You can use this hook to add anything to the site <head> but CSS and JavaScript files have their own methods so don't use this hook to add styles and scripts.

Take control of your WordPress instances by using the awesome hook system!