custom javascript in shopify code example
Example 1: how to add jquery to shopify
<!-- Include jQuery in your theme.liquid file, between <head> tag -->
<head>
<script
src="https://code.jquery.com/jquery-3.4.1.js"
integrity="sha256-WpOohJOqMqqyKL9FccASB9O0KwACQJpFTUBLTYOVvVU="
crossorigin="anonymous">
</script>
</head>
Example 2: custom js shopify
If I understand correctly, the asset_url filter is what you are looking for.
To include a JS file in a .liquid file, you use:
{{ 'script.js' | asset_url | script_tag }}
And a CSS file:
{{ 'style.css' | asset_url | stylesheet_tag }}