Promise methods javascript code example
Example 1: javascript promise
var promise = new Promise(function(resolve, reject) {
if () {
resolve("Stuff worked!");
}
else {
reject(Error("It broke"));
}
});
promise.then(
function(result) { },
function(error) { }
);
Example 2: js return a promise
function myAsyncFunction(url) {
return new Promise((resolve, reject) => {
const xhr = new XMLHttpRequest();
xhr.open("GET", url);
xhr.onload = () => resolve(xhr.responseText);
xhr.onerror = () => reject(xhr.statusText);
xhr.send();
});
}
Example 3: .then javascript
const promise2 = doSomething().then(successCallback, failureCallback);