javascript - 如何调用异步函数？

Question

我希望控制台先打印“1”，但我不确定如何调用异步函数并等待其执行，然后再转到下一行代码。

const request = require("request");

async function getHtml() {
  await request("https://google.com/", function (error, response, body) {
    console.log("1");
  });
}

getHtml();
console.log("2");

当然，我得到的输出是

2
1

Answer 1

根据 async_function MDN

Return value

A Promise which will be resolved with the value returned by the async function, or rejected with an uncaught exception thrown from within the async function.

async 函数总是返回一个 promise，你必须使用 .then() 或 await 来访问它的值

async function getHtml() {
  const request = await $.get('https://jsonplaceholder.typicode.com/posts/1')  
  return request
}

getHtml()
  .then((data) => { console.log('1')})
  .then(() => { console.log('2')});
  
// OR 

(async() => {
  console.log('1')
  await getHtml()  
  console.log('2')
})()

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>