What are Drupal Behaviors?

Drupal has a ‘behaviors’ system to provide a modular and better way for attaching JavaScript functionality to place elements on a page.  Drupal Behaviors allows you to override or extend the existing behavior. Find out how this Drupal core functionality helps.

Drupal is a versatile content management system that interlocks both the database and the server, which offers a revolutionary programming edge where there are options to insert the behavior to override JavaScript for an appealing interface. These Drupal behaviors are event triggered programs that get attached to the page elements to be changed. While behaviours can be attached to specific contents, multiple behaviours are also attached and can be ablazed multiple times for a quick remake.

Drupal behaviors handles infinite scroll’s AJAX call, since it has the ability to override or extend an existing behavior by a bouncing effect where it is an alternate for jQuery.ready.

It can be reattached and you can attach behaviors to a specific context. Drupal has a “behaviors” system to provide a modular and better way for attaching JavaScript functionality to place elements on a page. In short, the advantage of Behaviors over the document.ready() is that they are automatically re-applied to any content that is loaded through AJAX. 

Drupal 7 has two handles:

• To add an element to a page, you use ‘attach’

• To remove an element, you use ‘detach’

drupal.js has a $(document).ready() function that calls the Drupal.attachBehaviors() function, which, in turn, cycles through the Drupal.behaviors object, calling every one of its properties Drupal.behaviors runs when the document is ready and when Ajax calls are made. If you want to apply Java scripts to the elements during the page loads and all the elements are created using AJAX, Drupal.behaviors is the ideal solution.

With jQuery, you learn to put all your code inside the $(document).ready() function. When this is done, your code will run, manipulating elements and binding behaviors to events as per the instructions as soon as the DOM has  loaded. 

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