<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<script src="https://cdn.staticfile.org/react/16.4.0/umd/react.development.js"></script>
<script src="https://cdn.staticfile.org/react-dom/16.4.0/umd/react-dom.development.js"></script>
<script src="https://cdn.staticfile.org/babel-standalone/6.26.0/babel.min.js"></script>
</head>
<body>
<div id="app"></div>
<script type="text/babel">
class LoginForm extends React.Component{
constructor(props){
super(props)
// 初始化状态
this.state={
pwd:''
}
this.handleSubmit = this.handleSubmit.bind(this)
this.handleChange = this.handleChange.bind(this)
}
handleSubmit(event){
// 阻止默认提交
event.preventDefault()
const name = this.nameInput.value
const {pwd} = this.state
alert(`准备提交的用户名为${name},密码为${pwd}`)
}
handleChange(event){
// 1.读取输入的值
const pwd = event.target.value
// 2.更新状态
this.setState ({pwd})
}
render(){
return(
<form action="" onSubmit={this.handleSubmit}>
用户名：<input type="text" ref={input=>this.nameInput = input}/>
密码<input type="text" value={this.state.pwd} onChange={this.handleChange}/>
<input type="submit" value="登录"/>
</form>
)
}
}
ReactDOM.render(<LoginForm/>,document.getElementById('app'))
</script>
</body>
</html>
效果图
Video_2020-10-11_124132.gif
