如何在另一個類

Question

user.js的創建導入的類的實例

class User { 

    constructor() { 
    this.fisrtName 
    this.lastName 
    } 

    get fullName() { 
    `${this.firtName} ${this.lastName}` 
    } 

} 

export default User 

Test.js

import React from 'react' 
import {User} from './User' 

class Test extends React.Component { 

    testClick(e) { 
    const user = new User() //error! because User is undefined. 
    } 

    render() { 
    return (
     <button onClick={this.testClick.bind(this)}>test</button> 
    ) 
    } 

} 

export default Test 

Answer 1

變化

import {User} from './User' 

到

import User from './User' 

你的錯誤是，你正在默認出口：export default User內的user.js的模塊，但Test.js內的你正在命名進口：import {User} from './User'。