apply_filters( ‘script_loader_tag’, string $tag, string $handle, string $src )

User Contributed Notes

1. Skip to note 3 content

   opportus 8 years ago

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   Useful when a script excecution depends on “ attributes, eg:

   add_filter( 'script_loader_tag', 'add_id_to_script', 10, 3 );
   
   function add_id_to_script( $tag, $handle, $src ) {
       if ( 'dropbox.js' === $handle ) {
           $tag = '<script type="text/javascript" src="' . esc_url( $src ) . '" id="dropboxjs" data-app-key="MY_APP_KEY"></script>';
       }
   
       return $tag;
   }

   • Missing { on line 4.

     Sam Kent 6 years ago
   • Is it possible to do with Array? I have several Scripts that I want to do this, can I just replicate this code by changing the scripts? An Array would be better, right?

     ofmarconi 2 years ago
   • When I check this with PHPCS against the WordPress coding standard, it returns and error Scripts must be registered/enqueued via wp_enqueue_script()

     Peter Hebert 10 months ago
2. Skip to note 4 content

   Geoffrey Brossard 3 years ago

   You must log in to vote on the helpfulness of this noteVote results for this note: 1You must log in to vote on the helpfulness of this note

   It can be used to defer or async all JS scripts :

   function prefix_defer_js( $html ) {
       if ( ! is_admin() ) {
           $html = str_replace( '></script>', ' defer></script>', $html );
       }
       return $html;
   }
   add_filter( 'script_loader_tag', 'prefix_defer_js' );

   You can also use the $handle argument to filter scripts.

   • To expand on Geoffrey Brossard’s note, you might run into issues deferring all, the example below you can exclude the handles you might need from this filter like so:

        function prefix_defer_js($tag, $handle) {  	if (is_admin()) return $tag;  	 	$exclude_handles = [  	 		'heartbeat',  	 		'wp-hooks',  	 		'wp-auth-check',  	 		'jquery',  	 		'jquery-core',   			'jquery-ui-core',  	 		'wp-i18n'  	 	];  	 	if (in_array($handle, $exclude_handles)) {  	 		$tag = $tag;  	 	} else {  	 		$tag = str_replace('>', ' defer>', $tag);  	 	}   		return $tag;  	 }  	 add_filter('script_loader_tag', 'prefix_defer_js', 10, 2); 

     studiolxv 2 years ago