Enabling plugin on specific pages and subpages

Question

To increase the loading speed, I would like to only enable Event Manager plugin on the pages where it's actually used. For that, I wrote this piece of code:

// deregister unnecessary plugin scripts:
function my_deregister() {
    if ( !is_page('events') ) { 
        wp_deregister_script( 'events-manager' ); 
    }
}

add_action( 'wp_print_scripts', 'my_deregister', 100 );

However, the problem is that this event plugin creates a single page for each event and it needs to be enabled on those sub-pages, too. Apparently, each generated page is named differently. For instance, www.mysite.com/events/EventNameEventDate.

So I would like to have the plugin disabled on all pages except for 'events' and its sub-pages (of which I will obviously not always know the count and names). The is_page() works fine for the Events page but how do I modify it so that it recognises its sub-pages and enables the plugin scripts on them, too?

This was just a plugin specific example for easier understanding of the problem, but the question is generic and plugin independent.

Answer 1

You can get parent page slug and check like

global $post;
$post_data = get_post($post->post_parent);
$parent_slug = $post_data->post_name;
//echo $parent_slug;
if ( !is_page('events') || $parent_slug != 'events') {

Please try and let me know if any query

Answer 2

As Pratik Patel said in one if his comments. You can use is_singular( 'custom_post_type_name' ) to filter on CPT pages.

Since you are using Events Manager see this file from their plugin:
https://plugins.trac.wordpress.org/browser/events-manager/trunk/em-posts.php
On line 3 you see they define their CPT name as event.
So in your case you can use is_singular('event')

// deregister unnecessary plugin scripts:
function my_deregister() {
    if ( ! is_page('events') && ! is_singular('event') ) { 
        wp_deregister_script( 'events-manager' ); 
    }
}

add_action( 'wp_print_scripts', 'my_deregister', 100 );