ES6的模块化分为导出（export）与导入（import）两个模块，其中在项目中，我们会经常看到一种用法import * as obj from，这种写法是把所有的输出包裹到obj对象里

// index.js
export function fn1(data){undefined
  console.log(1)
}
export function fn2(data){undefined
  console.log(2)
}

import * as Fn from './index.js'
Fn.fn1()  // 1
Fn.fn2()  // 2

示例2

let myName = "Jon";
let myAge = 18;
let myfn = function(){undefined
    return "我是"+myName+"！今年"+myAge+"岁了"
}
export {undefined
    myName as name,
    myAge as age,
    myfn as fn
}

import {fn,age,name} from "./test.js";
consolelog(fn()); //我是Jon！今年19岁了
console.log(age); //19
consolelog(name); //Jon

或者

import * as info from "./test.js"; //通过*来批量接收，as 来指定接收的名字
console.log(info.fn()); //我是Jon！今年18岁了
console.log(info.age); //18
console.log(info.name); //Jon

总结：
import * as xxx from ‘xxx’: 会将若干export导出的内容组合成一个对象返回；
import xxx from ‘xxx’：（export default Din）只会导出这个默认的对象作为一个对象