What happens when a Promise is resolved?
resolve() method in JS returns a Promise object that is resolved with a given value. Any of the three things can happened: If the value is a promise then promise is returned. If the value has a “then” attached to the promise, then the returned promise will follow that “then” to till the final state.
How do I resolve a Promise in a for loop?
With a function passing itself as resolution-callback const delay = ms => new Promise(resolve => setTimeout(resolve, ms)); (function loop(i) { if (i >= 10) return; // all done delay(Math. random() * 1000). then(() => { console. log(i); loop(i+1); }); })(0);
How do you get data from a resolved Promise?
Consider the following code snippet: let primise = new Promise((resolve, reject) => { resolve({ x: 10 }); }); setTimeout(() => { // At some moment in the future (Promise is resolved) console. log(promise); }, 200);
How to handle promise inside loop in JavaScript?
The Promise.all method returns a promise when all the promises inside the promises array is resolved. So, this is how you can use promise inside a for each loop. A similar approach can be applied to use promise inside for loop or while in JavaScript or Node.js.
When to resolve a promise in JavaScript Stack Overflow?
Instead they should only be created at the time the preceding one resolves. Secondly, each promise that is created with new Promise needs to be resolved with a call to resolve (or reject ). This should be done when the timer expires. That will trigger any then callback you would have on that promise.
How to handle promise inside loop in NPM?
Create a folder called promise_loop. Initialize the project folder using npm. Create a file called helper.js which will make use of the request module to make the API calls.
How to return promise based on timeout in JavaScript?
As it may be a common thing to return a promise based on a timeout, you could create a separate function for generating such a promise. This is called promisifying a function, in this case setTimeout. It may improve the readability of the code: