Create WordPress Shortcodes

WordPress shortcodes are super handy, especially when handing off a WordPress-based website to a client. The alternative to using shortcodes is creating complicated templates, and even then, you cannot adequately replace what shortcodes can do. I recently needed to implement a new shortcode for the Mozilla Hacks blog and was happy to learn how simple the WordPress API makes creating new shortcodes! Let me show you how to create your own WordPress shortcodes!

First you start by creating a function within your theme's functions.php file. The function should return a string which replaces the shortcode within the rendered content. Your function can accept an $args argument which is a key=>value array of parameters passed in.

function my_shortcode_routine($args) {
 // $args = array('key1' => 'value1', 'key2' => 'value2')
 $return = '';

 // a bunch of logic and string-building here

 // return the result
 return $return;
}

Remember that your function shouldn't echo; a string must be returned.
After your function has been created, you can use WordPress' add_shortcode function to register the shortcode. The shortcode name function name doesn't need to match the shortcode:

// Add a shortcode called 'shortcode_name' that runs the 'my_shortcode_routine' function
add_shortcode('shortcode_name', 'my_shortcode_routine');

With the function created and the shortcode registered, now you can use said shortcode within your posts and pages:

[shortcode_name key1="value1" key2="value2"]

The shortcode system is positively beautiful; it's of large value to both seasoned devs and trained clients, and a prime example of why WordPress is deep and flexible platform.