If you need to load javascript by the case like domain name, following code solve your pain point.
Example 1) Loading script by the screen width
function addJavascript(jsname) {
var th = document.getElementsByTagName('head')[0];
var s = document.createElement('script');
s.setAttribute('type','text/javascript');
s.setAttribute('src',jsname);
th.appendChild(s);
}
if (screen.width > 500)
{
addJavascript("your_domain/js/jquery_computer.js");
}
else
{
addJavascript("your_domain/js/mobile_version.js");
}
Example 2) Loading Google Adsense script by the domain name
This is what actually I use for confluence having multiple space in different domain name.
<!-- Global site tag (gtag.js) - Google Analytics -->
<script>
function addJavascript(jsname) {
var th = document.getElementsByTagName('head')[0];
var s = document.createElement('script');
s.setAttribute('type','text/javascript');
s.setAttribute('src',jsname);
th.appendChild(s);
}
var sUA = "your default User Agent ID";
if (document.domain.toLowerCase()=="enewtown.com") sUA="UA-******-17"; else sUA="UA-*******-16";
addJavascript( "https://www.googletagmanager.com/gtag/js?id=" + sUA);
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
gtag('config', sUA);
</script>