es7 异步

第一种：
//异步处理
var testAsync = async function(){let aa = function(time){return new Promise((resolve,reject)=>{setTimeout(function () {var res = '5';resolve(res);}, time);})}console.log('1122')let result = await aa(1000);setTimeout(()=>{console.log(result)},0)console.log('end');}
testAsync();第二种：
// var sleep = function (time) {
//     return new Promise(function (resolve, reject) {
//         setTimeout(function () {
//         	var res = '5';
//             resolve(res);
//         }, time);
//     })
// };// var start = async function () {
// 		console.log('start')
//     let result = await sleep(1000);
//     console.log(result); 
// };
// start();