复制
1async function async1 () {
2  console.log('async1 start');
3  await new Promise(resolve => {
4    console.log('promise1')
5    resolve('promise resolve')
6  })
7  console.log('async1 success');
8  return 'async1 end'
9}
10console.log('srcipt start')
11async1().then(res => {
12  console.log(res)
13})
14new Promise(resolve => {
15  console.log('promise2')
16  setTimeout(() => {
17    console.log('timer')
18  })
19})
20