WordPress is not only a great blogging tool but a great content management platform that provides a lot of ways to let you hack into into its functionality to make it do whatever you want. Here are 12 lesser known wordpress hacks/ tricks that you might find useful for your next WordPress related project.
Most of these hacks require your WordPress template to have functions.php file, if it doesn’t exist, create one.
1. Add private notes to your WordPress blog posts
If you would like to add reference notes to your posts that will only be visible to authors of your blog, add this function to your theme’s functions.php file which will create a shortcode [note] so that you can add notes for authors by including them in [note] and [/note] while writing the post.
add_shortcode( 'note', 'sc_note' );
function sc_note( $atts, $content = null ) {
if ( current_user_can( 'publish_posts' ) )
return '<div class="note">'.$content.'</div>';
return '';
}
2. How to disable HTML in WordPress comments
WordPress allows some HTML tags like <a>, <em>, <strong> within comment text. But if you would like to disable this feature on your blog to prevent users from adding any HTML content within comment text, add this function to your theme’s functions.php file. This will treat the HTML content within comment text as literals and display them as it is.
// This will occur when the comment is posted
function plc_comment_post( $incoming_comment ) {
// convert everything in a comment to display literally
$incoming_comment['comment_content'] = htmlspecialchars($incoming_comment['comment_content']);
// the one exception is single quotes, which cannot be #039; because WordPress marks it as spam
$incoming_comment['comment_content'] = str_replace( "'", ''', $incoming_comment['comment_content'] );
return( $incoming_comment );
}
// This will occur before a comment is displayed
function plc_comment_display( $comment_to_display ) {
// Put the single quotes back in
$comment_to_display = str_replace( ''', "'", $comment_to_display );
return $comment_to_display;
}
add_filter( 'preprocess_comment', 'plc_comment_post', '', 1);
add_filter( 'comment_text', 'plc_comment_display', '', 1);
add_filter( 'comment_text_rss', 'plc_comment_display', '', 1);
add_filter( 'comment_excerpt', 'plc_comment_display', '', 1);
Source: How to disable HTML in WordPress Comments
3. Check if a WordPress plugin is active
You might sometime need to check whether a particular plugin is activated or not either to use its functionality or prevent any conflicts from occurring. WordPress provides a function is_plugin_active that accepts path to the plugin file and checks to see if plugin is activated or not.
<?php
if (is_plugin_active('plugin-directory/plugin-file.php')) {
//plugin is activated
}
?>
Source: Check if a WordPress Plugin is active – WpRecipes
4. Prevent Plugins from automatically loading stylesheets and scripts
Many plugins add their own stylesheets and scripts to your site to perform their function. But if you are using a lot of plugins on your WordPress blog, then this might lead to slow loading of your web pages as lots of scripts and stylesheets will require to be loaded first. What you can do to boost performance of your site while using plugins is combine their CSS and JavaScript files and prevent them to load on their own. For that you’ll need to look into plugin files and find out the handler names of all the CSS and JS files plugins are loading using wp_enqueue_script() and wp_enqueue_style() functions.
For example, if you use wp-pagenavi plugin, it loads its own stylesheet using the function:
wp_enqueue_style('wp-pagenavi', plugins_url('wp-pagenavi/pagenavi-css.css'), false, '2.50', 'all');
The first parameter to wp_enqueue_style() or wp_enqueue_script() is the name of handler for CSS or JS file.
In this case the handler name is wp-pagenavi. Now add these lines to your theme’s functions.php file to prevent it from loading.
//Prevent Stylesheets from loading
add_action( 'wp_print_styles', 'my_deregister_styles', 100 );
function my_deregister_styles() {
wp_deregister_style( 'wp-pagenavi' );
}
//Prevent JavaScript files from loading automatically
add_action( 'wp_print_scripts', 'my_deregister_javascript', 100 );
function my_deregister_javascript() {
wp_deregister_script( 'nameofhandler );
}
Source: How to Disable Scripts and Styles – Justin Tadlock
5. Showing Last Modified Date for a post
If you regularly update your old blog posts, then why not show the last modified date on the post page to let readers know when the post was last updated. Use this code to display the last modified date if the post has been modified at a later date.
Posted on <?php the_time('F jS, Y') ?>
<?php $u_time = get_the_time('U');
$u_modified_time = get_the_modified_time('U');
if ($u_modified_time != $u_time) {
echo "and last modified on ";
the_modified_time('F jS, Y');
echo ". "; } ?>
6. Custom Taxonomies in WordPress
By default, WordPress has two taxonomies categories and tags to group posts but custom taxonomies allow you to group your pages in your own custom ways, for example if you are running a movie review blog, you might want to add a taxonomy of genre to group movie review by genre, or a taxonomy of actors to group posts by actors. Custom taxonomies free you from restrictions of categories and tags.
You can add a custom taxonomy by adding this code to your theme’s functions.php file.
add_action( 'init', 'create_my_taxonomies', 0 );
function create_my_taxonomies() {
register_taxonomy( 'genre', 'post', array( 'hierarchical' => false, 'label' => 'Genre', 'query_var' => true, 'rewrite' => true ) );
register_taxonomy( 'actors', 'post', array( 'hierarchical' => false, 'label' => 'Actors', 'query_var' => true, 'rewrite' => true ) );
}
This will add new boxes to your add post page in admin panel if you are using WordPress 2.8+ using which you can add values for custom taxonomies. Justin Tadlock has written complete tutorial on how to create and use custom taxonomies, refer to it for more.
7. Create Post Only for your RSS Subscribers
If you would like to give an exclusive offer to your regular RSS subscribers, here’s a nice trick to create a post that is only visible to your RSS subscribers.
First of all, create a category that will hold posts to show to your RSS suscribers. For example, create a category ‘RSS’ and add some posts exclusively to it. Note down the category ID of this category. Now in your theme’s functions.php file, add these lines of code so that it is only shown to RSS subscribers.
<?php
function excludeCategory($query)
{
if($query->is_home | $query->is_archive )
//Exclude category from all other pages except RSS
$query->set('cat','-3');
return $query;
}
add_filter('pre_get_posts', 'excludeCategory');
?>
8. Get Rid of Curly quotes
WordPress usually replaces pair of double quotes with curly quotes e.g. “something” will become “somethingâ€. This is fine for most of the blogs and they look nice too but if you post source code in your posts, then you need to disable this functionality as it’ll also transform quotes within source code. Paste this code into your theme’s functions.php file.
<?php remove_filter('the_content', 'wptexturize'); ?>
Source: Get rid of Curly Quotes in WordPress Blog – WpRecipes
9. Deny Comment Posting to Spammers
You can keep a good number of spam comments away from your blog by checking the referrer URL of the posted comment form. Most of the spam comments are usually made by automated scripts and they just post the data to wp-comments-post.php so that there’s no referral URL through which form is submitted.
You can add a rule to your blog’s .htaccess file so that it restricts the access of wp-comments-post.php to requests that provide referral URL.
Here are the rules you need to add to .htaccess file. Do backup .htaccess file before modifying.
RewriteEngine On
RewriteCond %{REQUEST_METHOD} POST
RewriteCond %{REQUEST_URI} .wp-comments-post\.php*
RewriteCond %{HTTP_REFERER} !.*yourblog.com.* [OR]
RewriteCond %{HTTP_USER_AGENT} ^$
RewriteRule (.*) ^http://%{REMOTE_ADDR}/$ [R=301,L]
Source: How To Deny Comment Posting to no referrer requests – WpRecipes
Note: This will only prevent spam bots or automated scripts from posting comment and not those individuals that manually post them. You should use Akismet or other spam preventing tools in addition to this.
10. Insert Ads Within RSS Feed
Here’s a nice hack to add any HTML content into RSS Feeds like ads, copyright info or anything you want to show to just your RSS readers. Add this code to your theme’s functions.php file and you can customize the HTML content to anything you want to append or prepend to posts.
<?php
function insertAds($content) {
$content = $content.'<hr /><a href="http://webdeveloperplus.com">Visit WebDeveloper Plus for latest Web Design/Development Information</a>';
return $content;
}
add_filter('the_excerpt_rss', 'insertAds');
add_filter('the_content_rss', 'insertAds');
?>
11. Disable WordPress Feeds
If you are using WordPress as CMS which has just static content, then you might want to disable RSS feeds as it won’t be of any use for your users. Add this code to your functions.php file to disable RSS feeds.
function fb_disable_feed() {
wp_die( __('No feed available,please visit our <a href="'. get_bloginfo('url') .'">homepage</a>!') );
}
add_action('do_feed', 'fb_disable_feed', 1);
add_action('do_feed_rdf', 'fb_disable_feed', 1);
add_action('do_feed_rss', 'fb_disable_feed', 1);
add_action('do_feed_rss2', 'fb_disable_feed', 1);
add_action('do_feed_atom', 'fb_disable_feed', 1);
Source: Disable WordPress Feed – WpEngineer
12. Link Post Title to External URL
If you sometimes share just a link to other article out there which your readers might find useful, then here’s a nice hack to link the title of the post in your main template directly to the external URL. This will save your readers some time as they won’t have to open the post page just to find the resource link. Here’s how to do it:
Add these lines of code to functions.php file.
function print_post_title() {
global $post;
$thePostID = $post->ID;
$post_id = get_post($thePostID);
$title = $post_id->post_title;
$perm = get_permalink($post_id);
$post_keys = array(); $post_val = array();
$post_keys = get_post_custom_keys($thePostID);
if (!empty($post_keys)) {
foreach ($post_keys as $pkey) {
if ($pkey=='title_url') {
$post_val = get_post_custom_values($pkey);
}
}
if (empty($post_val)) {
$link = $perm;
} else {
$link = $post_val[0];
}
} else {
$link = $perm;
}
echo '<h2><a href="'.$link.'" rel="bookmark" title="'.$title.'">'.$title.'</a></h2>';
}
Next, you need to find out following lines in your theme’s index.php file:
<h2><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></h2>
Replace these lines with the following
<?php print_post_title() ?>
Now whenever you want to share an external URL, add a custom field to your post named title_url and set its value as the URL of the resource.
Source: WPBeginner