react小demo----烧水(函数与jsx结合)

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>react--父子组件通信</title>
	<script src='react.js'></script>
	<script src='react-dom.js'></script>
	<script src='babel.min.js'></script>
</head>
<body>
	<div id='example'></div>
	<script type='text/babel'>
		/*利用函数写一个烧水的demo*/
		/*需求:当小于0度,显示水结冰了
				大于80度,显示水烧开了
				其余显示正在加热中*/
		/*定义一个函数用来判断返回结果*/
		function show(now,max,min){
			var now = Number(now);
			var max = Number(max);
			var min = Number(min);
			if(now>max){
				return '水烧开了!';
			}else if(now<min){
				return '水结冰了!';
			}else{
				return '正在加热中!';
			}
		}
		class Cwater extends React.Component{
			constructor(){
				super();
				/*初始化一个状态来存储水的温度*/
				this.state = {
					wd:-2
				}
			}
			change(e){
				/*更新水温*/
				this.setState({
					wd:e.target.value
				});
			}
			render(){
				return (
					<div>
						<input type="number" defaultValue={this.state.wd} onChange={this.change.bind(this)}/>
						<h3>{show(this.state.wd,this.props.max,this.props.min)}</h3>
					</div>
				);
				
			}
		}
		ReactDOM.render(
			<Cwater max='80' min='0'/>,
			document.getElementById('example')

		);
			
		
	</script>
</body>
</html>

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转载自blog.csdn.net/hahahahahahahaha__1/article/details/80720956