Answers for "Promise"

5

promp node js

const readline = require("readline");

const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

rl.question("What is your name ? ", function saveInput(name) {
  console.log(`His name is ${name}`);
  rl.close();
});

rl.on("close", function saveInput() {
    console.log("\nBYE BYE !!!");
    process.exit(0);
});
Posted by: Guest on May-16-2020
14

js create a promise

/*
	A Promise is a proxy for a value not necessarily known when the promise is created. 
    It allows you to associate handlers with an asynchronous action's eventual success 
    value or failure reason.
*/            
let promise = new Promise((resolve , reject) => {
  fetch("https://myAPI")
    .then((res) => {
      // successfully got data
      resolve(res);
    })
    .catch((err) => {
      // an error occured
      reject(err);
    });          
});
Posted by: Guest on February-18-2020
3

javascript return promise

function doSomething() {
  return new Promise((resolve, reject) => {
    console.log("It is done.");
    // Succeed half of the time.
    if (Math.random() > .5) {
      resolve("SUCCESS")
    } else {
      reject("FAILURE")
    }
  })
}

const promise = doSomething(); 
promise.then(successCallback, failureCallback);
Posted by: Guest on June-04-2020
1

promise catch

//create a Promise
var p1 = new Promise(function(resolve, reject) {
  resolve("Success");
});

//Execute the body of the promise which call resolve
//So it execute then, inside then there's a throw
//that get capture by catch
p1.then(function(value) {
  console.log(value); // "Success!"
  throw "oh, no!";
}).catch(function(e) {
  console.log(e); // "oh, no!"
});
Posted by: Guest on April-03-2020
4

promise

new Promise( (res, rej) => {
  setTimeout(() => res(1), 1000);
}).then( (res) => {
  console.log(res); // 1
  return res*2
}).then( (res) => {
  console.log(res); // 2
});
Posted by: Guest on September-14-2021
0

Promise

let doSecond = () => {
  console.log('Do second.')
}

let doFirst = new Promise((resolve, reject) => {
  setTimeout(() => {
    console.log('Do first.')

    resolve()
  }, 500)
})

doFirst.then(doSecond)
Posted by: Guest on May-20-2021

Browse Popular Code Answers by Language