cychien

const p1 = Promise.resolve(42);
const p2 = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve(52);
  }, 100);
});

Promise.all([p1, p2])
  .then(msgs => {
     console.log(msgs[0]); //42

cychien

new Promise(resolve => {
	resolve(1);
	Promise.resolve().then(() => console.log(2));
	console.log(3);
}).then(t => console.log(t));

console.log(4);

cychien

const p = new Promise((resolve, reject) => {
  resolve(21);
})

p
  .then(v => {
    console.log(v); // 21
    return new Promise((resolve, reject) => {
      resolve(v * 2);
    });

cychien

function foo(x) {
  return new Promise((resolve, reject) => {
    //進行非同步任務
    //成功就呼叫resolve()
    //失敗就呼叫reject()
  });
} 

var p = foo(42);

cychien

foo(x) {
  //進行非同步任務
  return listener;
}

var evt = foo(42);

evt.on('completion', () => {
  //do something
});

cychien

analytics.trackPurchase(purchaseData, ()=> {
  chargeCreditCard();
  displayThankyouPage();
});

cychien

analytics.trackPurchase(purchaseData, ()=> {
  chargeCreditCard();
  displayThankyouPage();
});

cychien

analytics.trackPurchase(purchaseData, ()=> {
  chargeCreditCard();
  displayThankyouPage();
});

cychien

analytics.trackPurchase(purchaseData, ()=> {
  chargeCreditCard();
  displayThankyouPage();
});

cychien

analytics.trackPurchase(purchaseData, ()=> {
  chargeCreditCard();
  displayThankyouPage();
});