Two instances where this is ideal are:

• When loading an inline frame with Thickbox or Colorbox.
• When parsing AJAX requests in an external PHP file.

To further give justification for this technique, I had a major plugin conflict with another plugin. My Ajax Edit Comments plugin had failed to work for one of my clients.

After doing some troubleshooting, I determined it was a plugin conflict with “xyz” plugin. When I looked at the conflicting plugin’s code, I was able to pinpoint the problem to one patch of code, but failed to determine a fix.

The conflicting plugin was causing my nonces to fail, as well as my AJAX processor to fail (since that uses nonces as well).

Since my plugin’s editing options are all in a Colorbox inline frame (where I manually load the WordPress environment), I figured I would only load the plugins I needed (mine in this case).

Okay, enough chat! Let’s get started.

To call this technique a “hack” is a huge compliment. I wouldn’t recommend this for widespread use.

The Technique

If you look at your wp-settings.php file, there is a conditional right before it loads your active plugins.

It checks to see if the constant WP_INSTALLING is defined. If it is, WordPress doesn’t load any plugins.

So the trick to “trick” WordPress is to define the constant, and then manually load the WordPress environment.
After that, we can load any plugins desired.

Here’s some code:

<?php
header('Content-Type: text/html');
define('WP_INSTALLING', true);
//Adjust the dirnames to match the path to your wp-load file.
$root = dirname(dirname(dirname(dirname(dirname(__FILE__)))));
if (file_exists($root.'/wp-load.php')) {
		// WP 2.6
		require_once($root.'/wp-load.php');
} else {
		// Before 2.6
		require_once($root.'/wp-config.php');
}
$plugin = 'your-plugin-directory/your-plugin-file.php';
// Validate plugin filename
if ( !validate_file($plugin) && '.php' == substr($plugin, -4) && file_exists(WP_PLUGIN_DIR . '/' . $plugin)) {
	include_once(WP_PLUGIN_DIR . '/' . $plugin);
}
unset($plugin);
?>

You’ll see from the snippet above that we define the constant WP_INSTALLING, and then load the WordPress environment.

After WordPress has loaded, we load the plugin file we need.

If you need more than one plugin loaded, you can use a simple foreach statement.

$current_plugins = get_option( 'active_plugins' );
if ( is_array($current_plugins)) {
	foreach ( $current_plugins as $plugin ) {
        // $plugin looks like: your-plugin-dir/your-plugin-file.php
        switch($plugin) {
        	case: 'yourplugin':
            case: 'anotherplugin':
            	break;
             default:
             	continue;
        }
		if ( !validate_file($plugin) && '.php' == substr($plugin, -4) && file_exists(WP_PLUGIN_DIR . '/' . $plugin)) {
			include_once(WP_PLUGIN_DIR . '/' . $plugin);
		}
	}
	unset($plugin);
}
unset($current_plugins);

I would advise that you use this technique only in standalone files where needed, as I’m not sure of the long-term side-effects that might occur if the WP_INSTALLING constant is always defined.

Anyone who has used WordPress for any decent length of time probably knows that everything it outputs is in XHTML format. For those who prefer this, that’s just fine. However, for those of us out there that prefer to use HTML instead, we’re pretty much out of luck when it comes to WordPress. As it stands now, there is no easy way to make WordPress output in HTML format. But today I hope to help those people with this simple function I found around the web.

First, the code:

function HTMLify($buffer) {
    $xhtml = array('/XHTML 1.0 Transitional|XHTML 1.0 Strict|XHTML 1.0 Frameset|XHTML 1.1|XHTML Basic 1.0|XHTML Basic 1.1/', '/xhtml1\/DTD\/xhtml1-transitional.dtd|xhtml1\/DTD\/xhtml1-strict.dtd|xhtml11\/DTD\/xhtml11.dtd|xhtml-basic\/xhtml-basic10.dtd|xhtml-basic\/xhtml-basic11.dtd/', '/\/>/', '/\/\s+>/', '/xmlns="http:\/\/www.w3.org\/1999\/xhtml"/', '/\s+xmlns="http:\/\/www.w3.org\/1999\/xhtml"/', '/\s+xml:lang="(.*)"\s+lang="(.*)"/', '/\s+>/');
    $html = array('HTML 4.01', 'html4/strict.dtd', '>', '>', '', '', '', '>');
    return(preg_replace($xhtml, $html, $buffer));
}

Usage

1. Paste the code above in a file called functions.php inside the theme folder of your currently active theme.
2. Go into the theme folder of the currently active theme, open the header.php file, and paste this before any other code that outputs to the browser:
   <?php ob_start('HTMLify') ?>
   To use the default WordPress theme as an example, paste this code before the DOCTYPE declaration.
3. Save everything! That’s it! If you now look at the source code for your site you’ll notice that everything is HTML instead of XHTML.

Explanation

Basically, what the code does is, it takes the entire output of the page currently being requested and runs it through our function called HTMLify. The function looks for various XHTML-type code and replaces it with HTML-type code. Pretty simple.

The true beauty of it is the function happens after everything is output by WordPress. So, all of WordPress’s code AND any of your custom code is converted. So you could even continue to code in XHTML but have it output as HTML. Cool huh?

An Alternative

While looking around the web I also came upon this website which has a plugin for WordPress that does the same job. Those of you who prefer to use plugins may be more interested in this approach.

Anyway, that’s all there is to it. A little bit of code to solve a big problem. Enjoy!

I did! I was working on a project recently that needed a plugin. The only problem was that the plugin was inserting some unnecessary cruft into the header of my theme. So, I figured I’d just use the remove_filter function WordPress provides… right?

Hold on a second! It’s not working!? But I put in the function name just how the codex explains it:

remove_filter('wp_head', 'the_crufty_function');

Why would it not work? Time to do some troubleshooting… So, I opened up the main plugin PHP file in my code editor and began to look around. What’s this? It’s a class! Hmm… But why should that make a difference?

It seems that WordPress requires a special reference to the function if it is defined inside a class. If you, the reader, are at all familiar with PHP classes then you probably know that you can usually access a class’s functions like this:

$the_class_initiator_variable->some_function();

So, lets give that a try:

remove_filter('wp_head', $the_crufty_class->the_crufty_function);

Still nothing… Oh boy… What do I do now? I guess we’ll try some Googling…

…Hmm…

…Not finding much…

Well… after much searching and trying different things I finally came upon this:

remove_filter('wp_head', array(&$the_crufty_class, 'the_crufty_function'));

It works! Wonderful!

You take the class initiator variable and the name of the function and put it in an array. Simple as that!

Note: No, that ampersand is not a typo! It sets up a reference to the original variable instead of copying it’s value. You’d be surprised how many people don’t know what the ampersand does in PHP. I didn’t know for the longest time.

Also, because the remove_filter and remove_action functions are so similar this method applies to both.

There you have it! Just a quick little tip regarding an issue that doesn’t seem to be very well documented. I’m sure some of the experts out there already know of this but, I didn’t. I’m willing to assume there are some people out there like me who are racking their brains over this very issue.

Hope it helps!

Smashing Magazine has listed 10 Useful WordPress Hook Hacks in which they do some useful things by using the hook functionality. Many of these are already being performed by various plugins and by itself serves no new purpose. However, as a learning tool or as a catalyst for plugin authors to try new things, this list can be very useful. For example, the “Get entire post or page in a PHP variable” is similar to the technique used by Matt’s asides and later replicated in various Asides plugins written for WordPress.

Tips from that page that got me thinking (things that make you go hmmmmm?) include moving your wp-content directory, increasing your memory limit, changing the autosave interval, turning on debugging and finally the ability to specify a log file for errors. All of this through the wondrous wp-config.php file. The list is quite exhaustive.

While you are there, make sure you subscribe to the blog. Chris and Jeff are putting out some good stuff!

10 Exceptional WordPress hacks from Smashing Magazine.: Smashing Magazine has another list of nice hacks for WordPress including resizing images on the fly and automatically including the first image in your posts for your home page. These lists amaze me. Some of the more popular design sites and larger blog houses such as Smashing Magazine and Mashable have become very adept at using lists to link bait. These lists tend to get Dugg very heavily and bring in a lot of traffic for them. I still cannot look away from a good list about WordPress!

3 tools to track and defeat content theft lists three tools available to counteract content theft from your blog. This has become even more of an issue of late with the economy in the lurch, more people are jumping on the blogging bandwagon looking to make some extra money and might not be aware of copyright and Intellectual Property laws. The last tool listed is Tynt Tracer and I have been uysing it for a while. Tracer tracks and lists all the browser actions performed by visitors such as selecting and copying text and then uses Javascript to add a small link back to the original content if it is pasted onto another webpage somewhere. This method of tracking information copying is not really very effective, especially in this automated world of scrapers. While the information provided is interesting, it turns out to be a little useless if your content is not ruled by the lure of SEO but by your desire to just write and disseminate information. I still find myself checking back with the Tynt admin interface once in a while to see which topics seem to be more Search Engine popular this week.

20 Law related questions every blogger should know: Jonathan Bailey puts together the answers to a list of 20 Law related questions for bloggers for the topics of Copyright, Defamation and Trademark. Again, this is for informational purposes only and is not to be considered as legal advice. This is also based on US Law.

Learn some new tricks and discover new tools and plugins to speed up your WordPress blog. I have run into some scalability issues with this blog recently and have learned quite a bit.

Jean-Baptiste tells us about 10 awesome .htaccess hacks for your WordPress blog including the ability to redirect visitors to a maintenance page while you can continue to see and work on your blog.

New Features (and Some Comments)

• Landscape mode with extra wide keyboard
  
  This is probably the most desired feature for this application simply because it is physically painful to type a full length blog post in the iPhone portrait keyboard. I am glad that the portrait keyboard restriction is now a thing of the past!
• Link creation help
  
  
  I wasn’t sure where this feature was hiding at first, but I soon found the trick to invoking this feature. Basically anytime you are writing, you can type something that resembles a link (for example “www.” or “http”) to invoke a little prompt that asks you if you want to create a link. Answering yes will bring up another prompt asking you to fill in the URL. I think this is slick interface although some people might find it a bit annoying. It would be nice to merge these two dialogs into one dialog and also have the option to turn this feature off.
• Support for editing and creating pages
  
  There’s not much to say here. Previously you weren’t able to create/edit pages. Now you can. Note that this feature is only available for WordPress.org 2.7+ or WordPress.com blogs.
• Comment moderation
  
  This is one of my other favorite enhancements because I usually spend more time moderating comments than writing blog posts. To be able to do this on-the-go without having to continually login and deal with browser cookies is quite convenient. Note that this feature is only available for WordPress.org 2.7+ or WordPress.com blogs.
• Asynchronous publishing
  There weren’t any visible changes for this feature, but I assume asynchronous is better than what was in the earlier version.
• Photo resizing options
  
  When this feature is enabled, all photos attached to the post will be resized to be no larger than 640×480 to save space and publishing time. It’s a nice feature to have, but I don’t think I will be using it personally.

Bug in Version 1.2

I know that you are thinking, “already?” right? Indeed, the WordPress for iPhone App team has confirmed the existence of a photo bug in this version.  They are assuring us that the fix will be pushed out as soon as possible.  It’s best for you to wait on the upgrade if you post photos with the WordPress for iPhone application. If not, then you should definitely upgrade and enjoy these great new features! Version 1.21 is out with this bug fixed.  Go grab it now!

Go grab it!

You can get the WordPress for iPhone (and iPod touch) app for free at the iTunes App store.

WordPress excerpts, which are not excerpts, make a WordPress site easier to browse and its content easier to discover. In addition, when also used as META descriptions, good excerpts bring more and better traffic from search engines.

Topics discussed include:

1. What is the WordPress excerpt
2. Why write excerpts in WordPress
3. How to write excerpts
4. WordPress Excerpt Editor
5. Excerpts as META descriptions
6. Notes, Miscellaneous
7. Links

In Demetris’ style, the tutorial is very well written and well fleshed out.

• Send to Twitter (or consequently, send to Techmeme via Twitter)
• Create an RSS feed link
• Insert Adsense into a post
• Insert an RSS reader into a post
• Add shortcodes to sidebars

Please let us know if you have used any of these or know of/have created others that might be useful.

Mac OS X Status Bar integeration

Wordpress Notifier for Mac OSX.: This is a freeware tool that sits in your Mac OS X status bar and displays the current unapproved comment count on your WordPress blog. WordPress notifier works with WordPress 2.7 and above and works for blogs on WordPress.com. The screenshots look pretty cool!

Noupe has listed 11 new “Most Wanted” hacks for WordPress in a nice illustrated list. The new hacks include protecting your pictures from hotlinking and Custom Google Search for WordPress.

WPMU has received 37 nominations for their WordPress MU awards for 2008 and are looking for people to help choose the winners. View the nominations and vote for them.

Michael Kubler has written up a tutorial to make WordPress captioned images work as expected on your WordPress theme. Captioned images were introduced in WordPress 2.6 (I believe). This blog had the same problem till we managed to wrangle the extra CSS code for it to work.

Download Squad is linking to a Firefox add-on that allows a blogger to post screenshots/screengrabs directly to a WordPress blog. This can be very useful if you do a lot of reviews and such where you post screengrabs. Be wary of bugs.

I recently talked about a tutorial on creating Custom Write Panels in WordPress and thanks to WPCandy, have now found a pretty slick plugin that mimics that feature and adds a lot more. Flutter lets your modify your write page and post screens to your liking and adds the ability to add custom content types and write panels to these screens. From WP Candy’s review and from the Flutter documentation, it appears that the plugin is not only under active development and quite complex and mature, it also has a lot of potential for the future. For those that are planning to use Flutter, please remember that it is still in beta and there are lots of broken features and options. Upgrades and uninstallations seem to be the most fraught with issues.