Master de II. ULL. 1er cuatrimestre. 2020/2021
Here’s a callback-based function that loads a script from a specified src and adds it
to the current document:
1
2
3
4
5
6
7
8
9
function loadScript(src, callback) {
let script = document.createElement('script');
script.src = src;
script.onload = () => callback(null, script);
script.onerror = () => callback(new Error(`Script load error for ${src}`));
document.head.append(script);
}
Rewrite the loadScript function using promises.
Example of usage:
1
2
3
4
5
6
7
8
let promise = loadScript("https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.js");
promise.then(
script => alert(`${script.src} is loaded!`),
error => alert(`Error: ${error.message}`)
);
promise.then(script => alert('Another handler...'));