导出的根本用法

// 导出数据export let name = 'learn';export const age = 18;// 导出类export class Rect {    constructor(width, height){        this.width = width;        this.height = height;    }}// 导出函数export function sum(a, b){    return a + b;}

导入的根本语法

import {name, age, Rect, sum} from './example.js';// 不能给导入的绑定赋值,如 name = 'zhangsan'; 会报错

导入整个模块

import * as example from './example.js'// example 就蕴含了js文件里的全副export内容

import export 不容许呈现在其余语句或函数内,如if里。、

改名的状况

import {sum as add} from './example.js'