如何在 JS 中嵌套承诺并在不同时间解决它们？

Question

我认为运行数字 1、2 和 4 下面的代码会在 1 秒内依次显示在屏幕上。但是他们同时出现

由于我的嵌套解析在 setTimeout() 中，它们不应该只在前一个解析后一秒才解析吗？

var test = document.getElementById("test");

new Promise(function(resolve, reject) {
  setTimeout(() => resolve(1), 1000);
}).then(result => {
  test.innerHTML += result + "<br>";
  return new Promise(function(resolve, reject) {
    setTimeout(() => resolve(result * 2, 2000));
  });
}).then(result => {
  test.innerHTML += result + "<br>";
  return new Promise(function(resolve, reject) {
    setTimeout(() => resolve(result * 2, 3000));
  });
}).then(result => {
  test.innerHTML += result;
});

Answer 1

正确传递 setTimeout 的第二个参数

new Promise(function(resolve, reject) {
  setTimeout(() => resolve(1), 1000);
}).then(result => {
  console.log(result)
  return new Promise(function(resolve, reject) {
    setTimeout(() => resolve(result * 2),2000);
  });
}).then(result => {
 console.log(result)
  return new Promise(function(resolve, reject) {
    setTimeout(() => resolve(result * 2),3000);
  });
}).then(result => {
  console.log(result)
});

如何在 JS 中嵌套承诺并在不同时间解决它们？

How to nest promises in JS and have them resolved in different times?

javascript

asynchronous

settimeout

promise

es6-promise