Promise 简单实例一枚

<script>
function t(){
    return new Promise((resolve, reject)=>{
        setTimeout(()=>{
            resolve(0)
        },1000)
    })
}
function t1(){
    return new Promise((resolve, reject)=>{
        setTimeout(()=>{
            resolve(1)
        },1000)
    })
}
function t2(){
    return new Promise((resolve, reject)=>{
        setTimeout(()=>{
            resolve(2)
        },1000)
    })
}
t().then((e)=>{
    console.log(e)
    return t1()
}).then((e)=>{
    console.log(e)
	return t2()
}).then((e)=>{
    console.log(e)
});
</script>