How To Access Return Value Of Promise With Code Examples

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How To Access Return Value Of Promise With Code Examples

With this text, we’ll look at a number of completely different cases of the way to resolve the How To Access Return Value Of Promise downside.

const deal with = fetch("https://jsonplaceholder.typicode.com/customers/1")
  .then((response) => response.json())
  .then((person) => {
    return person.deal with;
  });

const printAddress = async () => {
  const a = await deal with;
  console.log(a);
};

printAddress();

As now we have seen, numerous examples had been utilised with a purpose to resolve the How To Access Return Value Of Promise downside that was current.

How do I get a returned worth from promise?

Promise resolve() methodology: If the worth is a promise then promise is returned. If the worth has a “then” hooked up to the promise, then the returned promise will comply with that “then” to until the ultimate state. The promise fulfilled with its worth can be returned.31-May-2022

What does return do in promise?

Returns a brand new Promise object that’s resolved with the given worth. If the worth is a thenable (i.e. has a then methodology), the returned promise will “comply with” that thenable, adopting its eventual state; in any other case, the returned promise can be fulfilled with the worth.04-Sept-2022

How do you utilize promise outcomes?

There are two methods to deal with promise outcomes: . then(), which is known as as a callback upon completion of the promise. async / await, which forces the present thread of execution to attend for the promise to finish.

How do you learn a promise worth in TypeScript?

To entry the worth of a promise in TypeScript, name the then() methodology on the promise, e.g. p. then(worth => console. log(worth)) . The then() methodology takes a operate, which is handed the resolved worth as a parameter.11-Mar-2022

Can an async operate return a worth?

Async capabilities at all times return a promise. If the return worth of an async operate is just not explicitly a promise, it is going to be implicitly wrapped in a promise. Note: Even although the return worth of an async operate behaves as if it is wrapped in a Promise.resolve , they aren’t equal.13-Sept-2022

Do I must return promise?

There is not any want to make use of a return assertion inside a brand new Promise() callback. The Promise constructor is just not anticipating any type of return worth from the callback. So, the rationale to make use of a return assertion inside that callback is just to regulate the circulation of execution in that operate.

Does await return a promise?

If a promise resolves usually, then await promise returns the end result. But within the case of a rejection, it throws the error, simply as if there have been a throw assertion at that line. In actual conditions, the promise could take a while earlier than it rejects. In that case there can be a delay earlier than await throws an error.06-Feb-2022

Do we want await with return?

However, if you wish to catch the rejected promise you are getting back from an asynchronous operate, then it’s best to undoubtedly use return await promise expression and add intentionally the await . catch(error) {} assertion catches solely awaited rejected guarantees in attempt {}09-Aug-2021

How do I do know if my promise is fulfilled?

You can use the promiseState operate under to verify whether or not a promise is fulfilled, rejected or nonetheless pending:

  • promiseState(promise, operate(state) { // `state` now both “pending”, “fulfilled” or “rejected” });
  • operate setTimer(delay) { return new Promise(resolve, reject) { setTimeout(resolve, delay) } }

Which is healthier promise or async await?

There are alternative ways to deal with the asynchronous code in NodeJS or in JavaScript that are: Callbacks.Javascript.

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