1. AJAX the WordPress way
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Justin Foell
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WordPress Developer @ 9seeds.com
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justin@9seeds.com
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@justinfoell
2. What is AJAX?
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Asynchronous JavaScript and XML
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A fast way of getting data or a portion of a
page from the web server w/o having to do a
full page request
3. How does AJAX work
(in WordPress)?
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jQuery makes an AJAX call to the server from
your browser
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WordPress routes the call appropriately
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The call is processed by WordPress core - or
a theme or plugin - which returns HTML or
JSON (JavaScript Object Notation) data
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Returned data is displayed appropriately
4. Required Pieces
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JavaScript (and form) on to trigger an AJAX
call
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WordPress hook (wp_ajax_* action) to route
the request
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A function to handle the request and return
the expected result
5. Dirty Details
Getting JavaScript/jQuery loaded
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Register & Enqueue your JavaScript using
wp_register_script & wp_enqueue_script
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Remember to include 'jquery' as a dependency when
registering your script, so it automagically gets loaded
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Use wp_localize_script to expose WordPress variables
to JavaScript – such as the ajax submit URL (only
needed for Front-End AJAX)
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AJAX calls always go to admin_url( 'admin-ajax.php' )
regardless if they're made from the front-end or wp-
admin
6. Dirty Details (cont.)
JavaScript/jQuery AJAX call
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Use jQuery AJAX Shorthand Methods
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The data object should have a member
variable called 'action' – the value of it will
correspond to the WordPress action
executed...
7. Dirty Details (cont.)
WordPress ajax hook
add_action( 'wp_ajax_<action-value>', 'function_to_run_on_ajax_call' );
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Should return valid HTML or JSON data
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You MUST exit or die!!!111one
8. WordPress Admin Example
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Almost the same as the front-end example
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Hook form into an existing page or add your
form to a custom wp-admin page
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Register & Enqueue javascript
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ajaxurl is already set
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Use json_encode in WordPress
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Use jQuery.parseJSON in jQuery
