Reactjs 在“为什么错误显示为这样”中-->';客户启动';没有定义
我正在从事react项目,我正在尝试使用react中的axios库将数据发布到数据库。但是我遇到了这样的错误-->“customerSignup”没有定义。我正在尝试解决此错误,但我没有,因此请帮助解决此错误,并帮助我将数据从前端发送到后端 这是App.jsReactjs 在“为什么错误显示为这样”中-->';客户启动';没有定义,reactjs,Reactjs,我正在从事react项目,我正在尝试使用react中的axios库将数据发布到数据库。但是我遇到了这样的错误-->“customerSignup”没有定义。我正在尝试解决此错误,但我没有,因此请帮助解决此错误,并帮助我将数据从前端发送到后端 这是App.js import React from 'react'; import './App.css'; import Navbar from './Components/Navbar/Navbar'; import Home from './Page
import React from 'react';
import './App.css';
import Navbar from './Components/Navbar/Navbar';
import Home from './Pages/Home/Home';
import Signup from './Pages/Signup/Signup';
import { BrowserRouter as Router,Switch,Route,} from "react-router-dom";
function App() {
return (
<div className="App">
<Router>
<Navbar></Navbar>
<Switch>
<Route exact path='/'><Home></Home></Route>
<Route path= '/signup'><Signup></Signup></Route>
</Switch>
</Router>
</div>
);
}
export default App;
从“React”导入React;
导入“/App.css”;
从“./Components/Navbar/Navbar”导入导航栏;
从“./Pages/Home/Home”导入主页;
从“./Pages/Signup/Signup”导入注册;
从“react Router dom”导入{BrowserRouter as Router,Switch,Route,};
函数App(){
返回(
);
}
导出默认应用程序;
这是Navbar.js
import React from 'react';
import './Navbar.css';
import { Link } from 'react-router-dom';
export default function Navbar() {
return (
<div className='container'>
<div className='row'>
<div className='col-12'>
<nav className="navbar navbar-expand-lg navbar-light bg-light">
<a className="navbar-brand" href="#">Navbar</a>
<button className="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
<span className="navbar-toggler-icon"></span>
</button>
<div className="collapse navbar-collapse" id="navbarNav">
<ul className="navbar-nav">
<li className="nav-item active">
<Link className='nav-link' to='/'>Home</Link>
</li>
<li className="nav-item">
<Link className='nav-link' to='/signup'>Signup</Link>
</li>
</ul>
</div>
</nav>
</div>
</div>
</div>
)
}
从“React”导入React;
导入“/Navbar.css”;
从'react router dom'导入{Link};
导出默认函数Navbar(){
返回(
-
家
-
报名
)
}
这是Signup.js
import React, { useState, useEffect } from 'react';
import axios from 'axios';
import './Signup.css';
export default function Signup() {
const Signup = () => {
const [customerSignUp, setCustomerSignUp] = useState([
{ email: '', password: '', firstName: '', lastName: ''}
]);
const handleChange = (event) => {
setCustomerSignUp({...customerSignup, [event.target.name]: event.target.value})
}
const handleSubmit = (e) => {
e.preventDefault()
axios.post('http://localhost:9000/api/signup', customerSignup)
.then(function (response) {
console.log(response)
})
.catch(function (error) {
console.log(error)
})
}
return (
<div className="container">
<form className='white' onSubmit={handleSubmit}>
<h5 className="grey-text.text-darken-3">Sign Up With Email</h5>
<div className="input-field">
<label htmlFor="lastName">Last Name</label>
<input type="text" name="lastName" value={customerSignUp.lastName} onChange={handleChange} required />
</div>
<div className="input-field">
<button className="btn blue darken-3" type="submit">Sign Up</button>
</div>
</form>
</div>
);
}
}
`````
import React,{useState,useffect}来自“React”;
从“axios”导入axios;
导入“./Signup.css”;
导出默认函数注册(){
常量注册=()=>{
const[customerSignUp,setCustomerSignUp]=useState([
{电子邮件:'',密码:'',名字:'',姓氏:'}
]);
常量handleChange=(事件)=>{
setCustomerSignUp({…customerSignup,[event.target.name]:event.target.value})
}
常量handleSubmit=(e)=>{
e、 预防默认值()
轴心柱http://localhost:9000/api/signup,customerSignup)
.然后(功能(响应){
console.log(响应)
})
.catch(函数(错误){
console.log(错误)
})
}
返回(
用电子邮件注册
姓
注册
);
}
}
`````
您的大写字母错误
更改此项:
const[customerSignUp,setCustomerSignUp]=…
为此:
const[customerSignup,setCustomerSignUp]=…
注意
Signup
和Signup
之间的拼写差异。还可以根据需要在代码的其他地方进行更改。Hi@Joshua Obritsch现在错误显示如下:注册(…):渲染时未返回任何内容。这通常意味着缺少返回语句。或者,要不呈现任何内容,请返回null。Removeconst Signup=()=>{
。