What is the best way to inject a javascript script from another domain into a page? (without using a
- by lowellk
Here is a snippet of javascript for loading a script onto a given page asynchronously. I was wondering if there was anything wrong with it? Can it be improved?
I haven't played with this yet, but some things I'm worried about are:
- cross browser support
- when script.readyState is true, will the old version of that function get clobbered?
- can i always count on there being a head or body element?
Here it is:
function injectScript(url, callback){
var script = document.createElement('script');
script.type = "text/javascript";
script.setAttribute('async', 'true');
script.src = url;
(document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(script);
if (callback) {
if (script.readyState){
script.onreadystatechange = function(){
if(script.readyState === "loaded" || script.readyState === "complete"){
script.onreadystatechange = null;
callback();
}
};
}else{
script.onload = function() {
callback();
}
}
}
}
