js之导入导出

导出

表达式式导出

// 导出变量/常量
export const name = 'hello'
export let addr = 'BeiJing City'
export var list = [1, 2 , 3]

// 导出函数
export function say (content){
  console.log(content);
}
export function run (){
  console.log('run')
}

// 导出对象
export ({
 code: 0,
 message: 'success'
})

// 导出类
export class Test {
  constructor(){
    this.id = 2
  }
}

对象式导出

// 导出变量/常量
const name = 'hello'
let addr = 'BeiJing City'
var list = [1, 2 , 3]
export {
	name,
	addr,
	list
}

// 导出函数
const say = (content) => {
	console.log(content);
}
let run = () => {
	console.log('run');
}
export {
	say,
	run
}

// 导出对象
let data = {
  code: 0,
  message: 'success'
}
export {
  data
}

// 导出类
class Test {
  constructor(){
    this.id = 2
  }
}
export {
  Test
}

默认导出

一个文件仅能有一个默认导出模块

例子见导入

导入

对默认导出模块的导入、修改导出/导入模块名称

const name = 'hello'
let addr = 'BeiJing City'
let phone = 1234567
var list = [1, 2 , 3]
export {
  name as cname,
  addr as caddr,
  phone
}
export default list

import list, {cname, caddr, phone as cphone } from A

整体导入

const name = 'hello'
let addr = 'BeiJing City'
var list = [1, 2 , 3]
export {
  name as cname,
  addr as caddr
}
export default list

import list, * as mod from A
console.log(list);
console.log(mod.cname);
console.log(mod.caddr);

或者

import * as mod from A
// 默认导出的变量被批量导出后，可通过属性名为default的变量中取出
console.log(mod.default);
console.log(mod.cname);
console.log(mod.caddr);