what's a promise javascript code example
Example 1: javascript promise
var promise = new Promise(function(resolve, reject) {
// do some long running async thing…
if (/* everything turned out fine */) {
resolve("Stuff worked!");
}
else {
reject(Error("It broke"));
}
});
//usage
promise.then(
function(result) { /* handle a successful result */ },
function(error) { /* handle an error */ }
);
Example 2: what is promise in javascript
Promises make async javascript easier as they are easy to use and write than callbacks. Basically , promise is just an object , that gives us either success of async opertion or failue of async operations
Example 3: javascript promises
firstRequest()
.then(function(response) {
return secondRequest(response);
}).then(function(nextResponse) {
return thirdRequest(nextResponse);
}).then(function(finalResponse) {
console.log('Final response: ' + finalResponse);
}).catch(failureCallback);