JavaScript异步代码

new Promise((resolve,reject) => {
    
    })

const responses = []
		for (const url of urls) {
    
    
			const response = fetch(url);
			responses.push(response)
		}
		await Promise.all(responses)

new Promise((resolve,reject) => {
    
    
			resolve(result)
		})

async onLoad() {
    
    
      let totalPosts = 0;
	  
      async function getPosts(userId) {
    
    
        const users = [{
    
     id: 1, posts: 5 }, {
    
     id: 2, posts: 3 }];
        await Math.random() * 1000;
        return users.find((user) => user.id === userId).posts;
      }
	  
      async function addPosts(userId) {
    
    
        const posts = await getPosts(userId);
        totalPosts += posts; // variable is read and immediately updated
      }
	  
      await Promise.all([addPosts(1), addPosts(2)]);
	  
      console.log('Post count:', totalPosts);
    }

const result1 = await asyncPromise1();
const result2 = await asyncPromise2(result1);
const result3 = await asyncPromise3(result2);
const result4 = await asyncPromise4(result3);
console.log(result4);

async () => {
    
    
  return getUser(userId);
}

async () => {
    
    
  try {
    
    
    const user = await getUser(userId);
    return user;
  } catch (error) {
    
    
    // Handle getUser error
  }
}

Promise.reject(new Error('An error occurred'));

function callback(err, data) {
    
    
  if (err) {
    
    
    console.log(err);
    return;
  }

  console.log(data);
}

const file = await fs.readFile(path);

async function getValue() {
    
    
  return someValue;
}

await getValue();

myPromise()
  .then(() => {
    
    })
  .catch(() => {
    
    });

const user = await getUserFromDB();
if (user) {
    
    }