async function async1() {
console.log('async1 start')
await async2()
console.log('async1 end')
}
async function async2() {
console.log('async2')
}
console.log('script start')
setTimeout(function () {
console.log('setTimeout')
}, 0)
async1();
new Promise
(function (resolve) {
console.log('promise1')
resolve();
})
.then(function () {
console.log('promise2')
})
console.log('script end')
执行结果
script start
async1 start
async2
promise1
script end
promise2
async1 end
undefined
setTimeout
