<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="x-ua-compatible" content="IE=edge" >
<title>promise</title>
</head>
<body>
<script>
async function aaa() {
console.log(1111)
return new Promise((resolve,reject)=>{
setTimeout(()=>{
console.log(123)
resolve(123)
},1000)
})
// setTimeout(()=>{
// // console.log(123)
// return 123
// },1000)
}
async function bbb() {
console.log(2222)
return new Promise((resolve,reject)=>{
setTimeout(()=>{
console.log(456)
resolve(456)
},1200)
})
// setTimeout(()=>{
// // console.log(456)
// return 456
// },1200)
}
async function ccc() {
console.log(3333)
return new Promise((resolve,reject)=>{
setTimeout(()=>{
console.log(789)
resolve(789)
},1400)
})
// setTimeout(()=>{
// // console.log(789)
// return 789
// },1400)
}
async function abc() {
let c = await ccc()
let b = await bbb()
let a = await aaa()
console.log(c)
console.log(b)
console.log(a)
}
// abc()
// let a = abc()
// 定义一个异步函数，3秒后才能获取到值(类似操作数据库)
function getSomeThing(){
return new Promise((resolve,reject)=>{
setTimeout(()=>{
resolve('获取成功')
},3000)
})
}
async function test(){
let a = await getSomeThing();
console.log(a)
}
// test();
const make = async()=>{
await bbb()
await ccc()
await aaa()
}
make()
</script>
</body>
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