Variable can be passed to jQuery or any javascript using wp_localize_script.
Example:
add_action( 'template_redirect', 'prefix_enqueue_vars' );
function prefix_enqueue_vars() {
$script_vars = array(
'setting_1' => get_option( 'some_option' ),
'setting_2' => get_option( 'another_option' ),
);
wp_enqueue_script( 'my_script', 'path/to/script.js', array( 'jquery' ), true);
wp_localize_script( 'my_script', 'unique_name', $script_vars );
}
How to get the variables in your javascript:
jQuery(document).ready(function($) {
$var_1 = unique_name.setting_1
$var_2 = unique_name.setting_2
});
WordPress will output your variables between <sript> </script> tags before enqueuing the javascript file so they will be available to use.
See wp_localize_script from Otto on WordPress for more information.
Edit:
Try adding the variables to a function that returns the value. I’m using the exact code below and it works.
wp_localize_script( 'cmb-scripts', 'MaxChar', array( 'charlimit' => c3m_get_the_size( $excerpt_length[0] ) ) );
The function that returns the variables below:
function c3m_get_the_size() {
global $post; global $prefix;
$box_size = get_post_meta( $post->ID, $prefix.'box_size', true );
if ( $box_size == 'single-single' ) { $excerpt_length = 150;
} elseif ( $box_size == 'single-double' ) { $excerpt_length = 150;
} elseif ( $box_size == 'single-triple' ) { $excerpt_length = 150;
}
return $excerpt_length;
}