我正在尝试创建一个导出多个ES6类的模块。我们假设我有以下目录结构:
my/
└── module/
├── Foo.js
├── Bar.js
└── index.js
Foo.js
和Bar.js
各自导出一个默认的ES6类:
// Foo.js
export default class Foo {
// class definition
}
// Bar.js
export default class Bar {
// class definition
}
我目前的index.js
设置如下:
import Foo from './Foo';
import Bar from './Bar';
export default {
Foo,
Bar,
}
但是,我无法导入。我希望能够做到这一点,但是没有找到这些课程:
import {Foo, Bar} from 'my/module';
在ES6模块中导出多个类的正确方法是什么?
答案 0 :(得分:160)
在您的代码中尝试此操作:
import Foo from './Foo';
import Bar from './Bar';
// without default
export {
Foo,
Bar,
}
不过,你也可以这样做:
// bundle.js
export { default as Foo } from './Foo'
export { default as Bar } from './Bar'
export { default } from './Baz'
// and import somewhere..
import Baz, { Foo, Bar } from './bundle'
使用export
export const MyFunction = () => {}
export const MyFunction2 = () => {}
const Var = 1;
const Var2 = 2;
export {
Var,
Var2,
}
// Then import it this way
import {
MyFunction,
MyFunction2,
Var,
Var2,
} from './foo-bar-baz';
与export default
的区别在于您可以导出内容,并在导入内容时应用名称:
// export default
export default class UserClass {
constructor() {}
};
// import it
import User from './user'
答案 1 :(得分:12)
希望这会有所帮助:
// Export (file name: my-functions.js)
export const MyFunction1 = () => {}
export const MyFunction2 = () => {}
export const MyFunction3 = () => {}
// Import
import * as myFns from "./my-functions";
myFns.MyFunction1();
myFns.MyFunction2();
myFns.MyFunction3();
// OR Import it as Destructured
import { MyFunction1, MyFunction2 } from "./my-functions";
// AND you can use it like below with brackets (Parentheses) if it's a function
// AND without brackets if it's not function (eg. variables, Objects or Arrays)
MyFunction1();
MyFunction2();
答案 2 :(得分:4)
@ webdeb的答案对我不起作用,我在用Babel编译ES6时遇到unexpected token
错误,执行命名的默认导出。
然而,这对我有用:
// Foo.js
export default Foo
...
// bundle.js
export { default as Foo } from './Foo'
export { default as Bar } from './Bar'
...
// and import somewhere..
import { Foo, Bar } from './bundle'
答案 3 :(得分:2)
// export in index.js
export { default as Foo } from './Foo';
export { default as Bar } from './Bar';
// then import both
import { Foo, Bar } from 'my/module';
答案 4 :(得分:2)
对于同一classes
文件中的多个 js
,从Component
扩展@wordpress/element
,您可以这样做:
// classes.js
import { Component } from '@wordpress/element';
const Class1 = class extends Component {
}
const Class2 = class extends Component {
}
export { Class1, Class2 }
并将它们导入另一个js
文件中:
import { Class1, Class2 } from './classes';
答案 5 :(得分:-1)
要导出类的实例,您可以使用以下语法:
// export index.js
const Foo = require('./my/module/foo');
const Bar = require('./my/module/bar');
module.exports = {
Foo : new Foo(),
Bar : new Bar()
};
// import and run method
const {Foo,Bar} = require('module_name');
Foo.test();