async await 初步接触

1/22/2018更新

async function sleep (val,time) {
    return new Promise ((resolve,reject) => {
        setTimeout(() => {
            console.log(val)
            resolve()
        }, time);
    })
}


async function fun () {
    await sleep(1,3000)
    await sleep(2,1000)

}


fun()

var sleep = function (time) {
    return new Promise(function (resolve, reject) {
        setTimeout(function () {
            console.log('1');
            resolve();
        }, time);
    })
};
var fun = function () {
    return new Promise((resolve,reject) => {
        setTimeout(() => {
            console.log('2');
            let a = 5;
            resolve(a);
        },2000)
    })
}
var fun2 = (x)=> {
    return new Promise((resolve,reject) => {
        setTimeout(() => {
            console.log(x);
            resolve();
        },1000);
        
    })
}

var go= async function () {
    console.log('start');
    await sleep(3000);
    let r = await fun();
    await fun2(r);
    console.log('end');
};

go();