state 和 props 主要的区别在于 props 是不可变的，而 state 可以根据与用户交互来改变。这就是为什么有些容器组件需要定义 state 来更新和修改数据。 而子组件只能通过 props 来传递数据。
demo1
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>菜鸟教程 React 实例</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>
<div id = "helloReactZzw"></div>
<script type="text/babel">
function HelloMessage(props) {
return <h1>Hello {props.name}!</h1>;
}
class HelloMessageZzw extends React.Component {
render() {
return (
<h1>Hello, {this.props.myname}</h1>
);
}
}
const element = <HelloMessage name="Runoob"/>;
const elementZzw = <HelloMessageZzw myname = "zzwLearningReact"/>;
//const elementZzw1 = <HelloMessageZzw myname = "zzwLearningReact"/> + <HelloMessage name="Runoob"/>;
//留一下一个问题下次思考
ReactDOM.render(
elementZzw,
document.getElementById(‘example‘)
);
</script>
</body>
</html>
demo2
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>菜鸟教程 React 实例</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>
<div id = "helloZzw"/>
<script type="text/babel">
class HelloMessage extends React.Component {
render() {
return (
<h1>Hello, {this.props.myname}</h1>
);
}
}
HelloMessage.defaultProps = {
name: ‘Runoob‘,
myname:‘zzw‘,
};
const element = <HelloMessage/>;
ReactDOM.render(
element,
document.getElementById(‘helloZzw‘)
);
</script>
</body>
</html>
原文地址：https://www.cnblogs.com/zzzzw/p/10462235.html
时间： 2024-10-08 09:37:55