Creating Your First
WordPress Plugin
Colin Loretz

Why?

codex.wordpress.org
Know it
Breathe it
Live it

Anatomy of a Plugin
Plugin Folder Name
• main php file
• js folder
• css folder
• php folder

Anatomy of a Plugin
reno-wordcamp
• reno-wordcamp.php
• js
• css
• php

Main PHP File
<?php
/*
Plugin Name: Your Plugin Name Here
Plugin URI: Your Plugin URI
Version: Current Plugin Version
Author: You
Description: What does this do?
*/

reno-wordcamp.php
<?php
/*
Plugin Name: Reno WordCamp
Plugin URI: http://renotahoewordcamp.com
Version: v1.0
Author: <a href = “http://colinloretz.com”>Colin Loretz</a>
Description: A plugin for Reno WordCamp
*/

Adding an Action
function addHeaderCode() {
echo ʻHello from the clouds!ʼ;
}

Actions & Filters
//Actions
add_action(ʻwp_headʼ, ʻaddHeaderCodeʼ, 1);
?>

Adding a Filter
function addContent($content=ʼʼ) {
$content .= ʻ<p>Colin is at WordCamp.</p>ʼ;
return $content;
}

Actions & Filters
//Actions
add_action(ʻwp_headʼ, ʻaddHeaderCodeʼ, 1);
//Filters
add_filter(ʻthe_contentʼ, ʻaddContentʼ);
?>

Adding a Shortcode
[renowordcamp]

Adding a Shortcode
function renoShortcode($att) {
extract(shortcode_atts(array(
'foo' => 'no foo',
'bar' => 'default bar',
), $atts));
return \"foo = {$foo}\";
}

Add the Shortcode
//Actions
add_action(ʻwp_headʼ, ʻaddHeaderCodeʼ, 1);
//Filters
add_filter(ʻthe_contentʼ, ʻaddContentʼ);
//Shortcodes
add_shortcode('renowordcamp', 'renoShortcode');

Going Further
Saving & Storing Explore Plugins
Learn from others
Options
Post Metadata
Database

Want More?
• Wordpress.org (and codex)
• WP-Hacker email list (google it)
• WordPress Planet

Find Me
@colinloretz
www.colinloretz.com