In JavaScript how do I/should I use async/await with XMLHttpRequest?

Question

Full disclosure: I\'d qualify myself as having intermediate JavaScript knowledge. So this is slightly above my experience level at this time.

I\'ve got a Google Chro

Answer 1

I usually do async/await like this:

async function doAjaxThings() {
    // await code here
    let result = await makeRequest("GET", url);
    // code below here will only execute when await makeRequest() finished loading
    console.log(result);
}
document.addEventListener("DOMContentLoaded", function () {
    doAjaxThings();
    // create and manipulate your DOM here. doAjaxThings() will run asynchronously and not block your DOM rendering
    document.createElement("...");
    document.getElementById("...").addEventListener(...);
});

Promisified xhr function here:

function makeRequest(method, url) {
    return new Promise(function (resolve, reject) {
        let xhr = new XMLHttpRequest();
        xhr.open(method, url);
        xhr.onload = function () {
            if (this.status >= 200 && this.status < 300) {
                resolve(xhr.response);
            } else {
                reject({
                    status: this.status,
                    statusText: xhr.statusText
                });
            }
        };
        xhr.onerror = function () {
            reject({
                status: this.status,
                statusText: xhr.statusText
            });
        };
        xhr.send();
    });
}