React组件状态更新实践-优快云博客

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Hello React!</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="example"></div>
<script type="text/babel">
var a=(<h1>hello,world!</h1>)
var c=(<h1>hello,China!</h1>)
var D=p=><h1>{p.b}</h1>
var f=g=><D b={g} />
class E extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
		com: a,
		b:'hahaha...'
	};
  }
	//三者具有同样的效果，个人觉得第二种是最好的
	b=()=>this.setState({com:<D b={this.state.b} />});
	//b=()=>this.setState({com:D(this.state)});
	//b=()=>this.setState({com:f(this.state.b)});	
		  
		
		
  render() {
    return (
      <div onClick={this.b}>
        {this.state.com}
      </div>
    );
  }
}
ReactDOM.render(
    <E />,
    document.getElementById('example')
);
</script>
 
</body>
</html>