Promise javascript simple sample

by marbx

JavaScript

var isGood = true;

// Promise

function checkIfGoodStyle1(input) {
  return new Promise(
    (resolve, reject) => {
      if (input) {
        //expensive operations.......
        var result = 'Patient treated successfully';
        resolve(result); // fulfilled
      } else {
        var reason = new Error('Next appointment please');
        reject(reason); // reject
      }

    }
  );
}
var checkIfGood = new Promise(
  function(resolve, reject) {
    if (isGood) {
      //expensive operations.......
      var result = 'Patient treated successfully';
      resolve(result); // fulfilled
    } else {
      var reason = new Error('Next appointment please');
      reject(reason); // reject
    }

  }
);

//checkIfGood.then((result)=>console.log(result));
checkIfGood.then(result => {
  console.log(result);
}, failure => {
  console.log(failure.name + "-" + failure.message);
})
checkIfGoodStyle1(false).then(result => {
  console.log(result);
}, failure => {
  console.log(failure.name + "-" + failure.message);
})

//var f = checkIfGoodStyle1(false).then(result => (f=result), failure => (f=failure));

let delayPromise = new Promise(resolve => setTimeout(resolve, 3000));
delayPromise.then(() => {
  //somethng
});