2021-07-08

<!-- 引入react核心库 -->
<script type="text/javascript" src="../js/react.development.js"></script>
<!-- 引入react-dom，用于支持react操作DOM -->
<script type="text/javascript" src="../js/react-dom.development.js"></script>
<!-- 引入babel，用于将jsx转为js -->
<script type="text/javascript" src="../js/babel.min.js"></script>

<script type="text/babel">
	//创建组件
	class Demo extends React.Component{

		state = {isHot:false}

		showInfo = ()=>{
			const {input1} = this
			alert(input1.value)
		}

		changeWeather = ()=>{
			//获取原来的状态
			const {isHot} = this.state
			//更新状态
			this.setState({isHot:!isHot})
		}

		saveInput = (c)=>{
			this.input1 = c;
			console.log('@',c);
		}

		render(){
			const {isHot} = this.state
			return(
				<div>
					<h2>今天天气很{isHot ? '炎热':'凉爽'}</h2>
					{/*<input ref={(c)=>{this.input1 = c;console.log('@',c);}} type="text"/><br/><br/>*/}
					<input ref={this.saveInput} type="text"/><br/><br/>
					<button onClick={this.showInfo}>点我提示输入的数据</button>
					<button onClick={this.changeWeather}>点我切换天气</button>
				</div>
			)
		}
	}
	//渲染组件到页面
	ReactDOM.render(<Demo/>,document.getElementById('test'))
</script>