如何在WordPress中加入jquery脚本

Question

I'm trying to load a simple jQuery script into a WP footer (using an Avada child theme). I've done it before, but nothing's happening. Can anyone spot my error?

In functions.php :

add_action( 'wp_enqueue_scripts', 'wpalert' ); 
function wpalert() {
wp_register_script('wpalert', '--hardcoded root--', array ( 'jquery' ), null, true);
wp_enqueue_script('wpalert');
}

In my .js file:

$(document).ready(function(){
  alert("test");
})

Answer 1

There are 2 things that you need to change:

1) wp_enqueue_script('wpalert');

By wordpress documentation, you must use the pattern:

function my_function_scripts() {
    wp_enqueue_script( 'wpalert', get_template_directory_uri() . '/js/wpalert.js', array('jquery'));
}

add_action( 'wp_enqueue_scripts', 'my_function_scripts' );

2) To use jQuery in Wordpress, you need to use no conflict mode:

// $() will be the alias for jQuery()
jQuery( document ).ready( function( $ ) {

} );

More references: https://developer.wordpress.org/reference/functions/wp_enqueue_script/