Javascript: Detecting script load completion

Question

I'm dynamically adding script usign:

var el = document.createElement("script");
document.getElementsByTagname("head")[0].appendChild(el);

It seems neither script.onload nor document.onreadystatechange could be used to determine the end of loading process. How should I catch dynamic script load completion?

Answer 1

The onload event needs to be attached before setting the script's src, which is what causes the script to start loading.

Example:

var el = document.createElement("script");
el.onload = function() {
    // Script is loaded
}
el.src = ...