JavaScript Promises Using ES2017 async/await
Example
The same example above, Image loading, can be written using async functions. This also allows using the common try/catch method for exception handling.
function loadImage(url) {
return new Promise((resolve, reject) => {
const img = new Image();
img.addEventListener('load', () => resolve(img));
img.addEventListener('error', () => {
reject(new Error(`Failed to load ${url}`));
});
img.src = url;
});
}
(async () => {
// load /image.png and append to #image-holder, otherwise throw error
try {
let img = await loadImage('http://example.com/image.png');
document.getElementById('image-holder').appendChild(img);
}
catch (error) {
console.error(error);
}
})();
