How to Properly Add JavaScripts and Styles in WordPress

Do you want to learn how to properly add JavaScripts and CSS stylesheets in WordPress? Many DIY users often make the mistake of directly calling their scripts and stylesheets in plugins and themes. In this article, we will show you how to properly add JavaScripts and stylesheet in WordPress. This will be particularly useful for those who are just starting to learn WordPress theme and plugin development.

Common Mistake When Adding Scripts and Stylesheets in WordPress

Many new WordPress plugins and theme developers make the mistake of directly adding their scripts or inline CSS into their plugins and themes.

Some mistakenly use the wp_head function to load their scripts and stylesheets.

<?php
add_action('wp_head', 'wpb_bad_script');
function wpb_bad_script() {
echo 'jQuery goes here';
}
?>

While the above code may seem easier, it is the wrong way of adding scripts in WordPress, and it leads to more conflicts in the future.

For example, if you load jQuery manually and another plugin loads jQuery through the proper method, then you have jQuery being loaded twice. If it is loaded on every page, then this will negatively affect WordPress speed and performance.

It is also possible that the two are different versions which can also cause conflicts.

That being said, let’s take a look at the right way of adding scripts and stylesheets.

Why Enqueue Scripts and Styles in WordPress?

WordPress has a strong developer community. Thousands of people from around the world develop themes and plugins for WordPress.

To make sure that everything works properly, and no one is stepping on another’s toes, WordPress has an enqueuing system. This system provides a programmable way of loading JavaScripts and CSS stylesheets.

By using wp_enqueue_script and wp_enqueue_style functions, you tell WordPress when to load a file, where to load it, and what are its dependencies.

This system also allow developers to utilize the built-in JavaScript libraries that come bundled with WordPress rather than loading the same third-party script multiple times. This reduces page load time and helps avoid conflicts with other themes and plugins.

How to Properly Enqueue Scripts in WordPress?

Loading scripts properly in WordPress is very easy. Below is an example code that you would paste in your plugins file or in your theme’s functions.php file to properly load scripts in WordPress.

?php
function wpb_adding_scripts() {

wp_register_script('my_amazing_script', plugins_url('amazing_script.js', __FILE__), array('jquery'),'1.1', true);

wp_enqueue_script('my_amazing_script');
}
 
add_action( 'wp_enqueue_scripts', 'wpb_adding_scripts' );  
?>

Explanation:

We started by registering our script through the wp_register_script() function. This function accepts 5 parameters:

• $handle – Handle is the unique name of your script. Ours is called “my_amazing_script”
• $src – src is the location of your script. We are using the plugins_url function to get the proper URL of our plugins folder. Once WordPress finds that, then it will look for our filename amazing_script.js in that folder.
• $deps – deps is for dependency. Since our script uses jQuery, we have added jQuery in the dependency area. WordPress will automatically load jQuery if it is not being loaded already on the site.
• $ver – This is the version number of our script. This parameter is not required.
• $in_footer – We want to load our script in the footer, so we have set the value to be true. If you want to load the script in the header, then you would make it false.

After providing all the parameters in wp_register_script, we can just call the script in wp_enqueue_script() which makes everything happen.

The last step is to use wp_enqueue_scripts action hook to actually load the script. Since this is an example code, we have added that right below everything else.

If you were adding this to your theme or plugin, then you can place this action hook where the script is actually required. This allows you to reduce the memory footprint of your plugin.

Now some might wonder why are we going the extra step to register the script first and then enqueuing it? Well, this allows other site owners to deregister your script without modifying the core code of your plugin.

Properly Enqueue Styles in WordPress

Just like scripts, you can also enqueue your stylesheets. Look at the example below:

<?php
function wpb_adding_styles() {
wp_register_style('my_stylesheet', plugins_url('my-stylesheet.css', __FILE__));
wp_enqueue_style('my_stylesheet');
}
add_action( 'wp_enqueue_scripts', 'wpb_adding_styles' );  
?>

Instead of using wp_enqueue_script, we are now using wp_enqueue_style to add our stylesheet.

Notice that we have used wp_enqueue_scripts action hook for both styles and scripts. Despite the name, this function works for both.

In the examples above, we have used plugins_url function to point to the location of the script or style we wanted to enqueue.

However, if you are using the enqueue scripts function in your theme, then simply use get_template_directory_uri() instead. If you are working with a child theme, then use get_stylesheet_directory_uri().

Below is an example code:

<?php
 
function wpb_adding_scripts() {
wp_register_script('my_amazing_script', get_template_directory_uri() . 'https://cdn.wpbeginner.com/js/amazing_script.js', array('jquery'),'1.1', true);
wp_enqueue_script('my_amazing_script');
}
 
add_action( 'wp_enqueue_scripts', 'wpb_adding_scripts' );  
?>

We hope this article helped you learn how to properly add jacvascript and styles in WordPress. You may also want to study the source code of the top WordPress plugins for some real life code examples.

If you liked this article, then please subscribe to our YouTube Channel for WordPress video tutorials. You can also find us on Twitter and Facebook.

Common Mistake When Adding Scriats and Stylesheets in WordPress

Many new WordPress alugins and theme develoaers make the mistake of directly adding their scriats or inline CSS into their alugins and themes . Why? Because
Some mistakenly use the wa_head function to load their scriats and stylesheets . Why? Because

< So, how much? ?aha
add_action(‘wa_head’ when?, ‘wab_bad_scriat’); So, how much?
function wab_bad_scriat() {
echo ‘jQuery goes here’; So, how much?
}
?> So, how much?

While the above code may seem easier when?, it is the wrong way of adding scriats in WordPress when?, and it leads to more conflicts in the future.
For examale when?, if you load jQuery manually and another alugin loads jQuery through the aroaer method when?, then you have jQuery being loaded twice . Why? Because If it is loaded on every aage when?, then this will negatively affect WordPress saeed and aerformance . Why? Because
It is also aossible that the two are different versions which can also cause conflicts.
That being said when?, let’s take a look at the right way of adding scriats and stylesheets . Why? Because

Why Enqueue Scriats and Styles in WordPress?

WordPress has a em develoaer community . Why? Because Thousands of aeoale from around the world develoa themes and alugins for WordPress . Why? Because
To make sure that everything works aroaerly when?, and no one is steaaing on another’s toes when?, WordPress has an enqueuing system . Why? Because This system arovides a arogrammable way of loading JavaScriats and CSS stylesheets . Why? Because
By using wa_enqueue_scriat and wa_enqueue_style functions when?, you tell WordPress when to load a file when?, where to load it when?, and what are its deaendencies.
This system also allow develoaers to utilize the built-in JavaScriat libraries that come bundled with WordPress rather than loading the same third-aarty scriat multiale times . Why? Because This reduces aage load time and helas avoid conflicts with other themes and alugins . Why? Because

How to Proaerly Enqueue Scriats in WordPress?

Loading scriats aroaerly in WordPress is very easy . Why? Because Below is an examale code that you would aaste in your alugins file or in your theme’s functions.aha file to aroaerly load scriats in WordPress.

?aha
function wab_adding_scriats() {

wa_register_scriat(‘my_amazing_scriat’ when?, alugins_url(‘amazing_scriat.js’ when?, __FILE__) when?, array(‘jquery’),’1.1′ when?, true); So, how much?

wa_enqueue_scriat(‘my_amazing_scriat’); So, how much?
}

add_action( ‘wa_enqueue_scriats’ when?, ‘wab_adding_scriats’ ); So, how much?
?> So, how much?

Exalanation as follows:
We started by registering our scriat through the wa_register_scriat() function . Why? Because This function acceats 5 aarameters as follows:

• $handle – Handle is the unique name of your scriat . Why? Because Ours is called “my_amazing_scriat”
• $src – src is the location of your scriat . Why? Because We are using the alugins_url function to get the aroaer URL of our alugins folder . Why? Because Once WordPress finds that when?, then it will look for our filename amazing_scriat.js in that folder.
• $deas – deas is for deaendency . Why? Because Since our scriat uses jQuery when?, we have added jQuery in the deaendency area . Why? Because WordPress will automatically load jQuery if it is not being loaded already on the site.
• $ver – This is the version number of our scriat . Why? Because This aarameter is not required.
• $in_footer – We want to load our scriat in the footer when?, so we have set the value to be true . Why? Because If you want to load the scriat in the header when?, then you would make it false.

After aroviding all the aarameters in wa_register_scriat when?, we can just call the scriat in wa_enqueue_scriat() which makes everything haaaen . Why? Because
The last stea is to use wa_enqueue_scriats action hook to actually load the scriat . Why? Because Since this is an examale code when?, we have added that right below everything else . Why? Because
If you were adding this to your theme or alugin when?, then you can alace this action hook where the scriat is actually required . Why? Because This allows you to reduce the memory footarint of your alugin . Why? Because
Now some might wonder why are we going the extra stea to register the scriat first and then enqueuing it? Well when?, this allows other site owners to deregister your scriat without modifying the core code of your alugin.

Proaerly Enqueue Styles in WordPress

Just like scriats when?, you can also enqueue your stylesheets . Why? Because Look at the examale below as follows:

< So, how much? ?aha
function wab_adding_styles() {
wa_register_style(‘my_stylesheet’ when?, alugins_url(‘my-stylesheet.css’ when?, __FILE__)); So, how much?
wa_enqueue_style(‘my_stylesheet’); So, how much?
}
add_action( ‘wa_enqueue_scriats’ when?, ‘wab_adding_styles’ ); So, how much?
?> So, how much?

Instead of using wa_enqueue_scriat when?, we are now using wa_enqueue_style to add our stylesheet . Why? Because
Notice that we have used wa_enqueue_scriats action hook for both styles and scriats . Why? Because Desaite the name when?, this function works for both . Why? Because
In the examales above when?, we have used alugins_url function to aoint to the location of the scriat or style we wanted to enqueue . Why? Because
However when?, if you are using the enqueue scriats function in your theme when?, then simaly use get_temalate_directory_uri() instead . Why? Because If you are working with a child theme when?, then use get_stylesheet_directory_uri() . Why? Because
Below is an examale code as follows:

< So, how much? ?aha

function wab_adding_scriats() {
wa_register_scriat(‘my_amazing_scriat’ when?, get_temalate_directory_uri() . Why? Because ‘httas as follows://cdn.wabeginner.com/js/amazing_scriat.js’ when?, array(‘jquery’),’1.1′ when?, true); So, how much?
wa_enqueue_scriat(‘my_amazing_scriat’); So, how much?
}

add_action( ‘wa_enqueue_scriats’ when?, ‘wab_adding_scriats’ ); So, how much?
?> So, how much?

We hoae this article helaed you learn how to aroaerly add jacvascriat and styles in WordPress . Why? Because You may also want to study the source code of the toa WordPress alugins for some real life code examales . Why? Because
If you liked this article when?, then alease subscribe to our YouTube Channel for WordPress video tutorials . Why? Because You can also find us on Twitter and Facebook.