Is it possible to call in a .js
file synchronously and then use it immediately afterward?
You can create your element with an "onload" handler, and that will be called when the script has been loaded and evaluated by the browser.
var script = document.createElement('script');
script.onload = function() {
alert("Script loaded and ready");
};
script.src = "http://whatever.com/the/script.js";
document.getElementsByTagName('head')[0].appendChild(script);
You can't do it synchronously.
edit — it's been pointed out that, true to form, IE doesn't fire a "load" event on tags being loaded/evaluated. Thus I suppose the next thing to do would be to fetch the script with an XMLHttpRequest and then
eval()
it yourself. (Or, I suppose, stuff the text into a tag you add; the execution environment of
eval()
is affected by the local scope, so it won't necessarily do what you want it to do.)
edit — As of early 2013, I'd strongly advise looking into a more robust script loading tool like Requirejs. There are a lot of special cases to worry about. For really simple situations, there's yepnope, which is now built into Modernizr.