Normally what you would do is to use one file for all of the pages javascripts to reduce the overhead of multiple HTTP calls, or have some other mechanism in place (e.g. #include page, ~bundles), or just do the 5 different script elements.
Doing some searching I found some code on Stack Overflow that may help
Dynamic Script Loading
You could add a script tag with the script URL into the HTML. To avoid the overhead of jQuery, this is an ideal solution.
The script can even reside on a different server. Furthermore, the browser evaluates the code. The {script} tag can be injected into either the web page {head}, or inserted just before the closing {body} tag.
From this I came up with this which is based on the provided code and added in your 5 sample files. You may need to work with getting the URLs to resolve properly, I myself would use fully qualified ones. And naturally you could put this in a completely separate file.
function LoadScript(url) {
var script = document.createElement("script");
script.src = url;
document.head.appendChild(script);
}
LoadScript("Scripts/ajax.js");
LoadScript("Scripts/cookie.js");
LoadScript("Scripts/font_sizing.js");
LoadScript("Scripts/event_handling.js");
LoadScript("Scripts/utilities.js");
Source:
How do I include a JavaScript file in another JavaScript file? - Stack Overflow[
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