列表渲染
image.png
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>计数器</title>
<style>
.item {
margin: 10px;
padding: 0 20px;
border: 1px solid orange;
}
</style>
</head>
<body>
<div id="root"></div>
<script src="../lib/react.js"></script>
<script src="../lib/react-dom.js"></script>
<script src="../lib/babel.js"></script>
<script type="text/babel">
// 1.定义App根组件
class App extends React.Component {
constructor() {
super()
this.state = {
students: [
{ id: 111, name: "why", score: 199 },
{ id: 112, name: "kobe", score: 98 },
{ id: 113, name: "james", score: 199 },
{ id: 114, name: "curry", score: 188 },
]
}
}
render() {
const { students } = this.state
// 分数大于100的学生进行展示
const filterStudents = students.filter(item => {
return item.score > 100
})
// 分数大于100, 只展示两个人的信息
// slice(start, end): [start, end)
const sliceStudents = filterStudents.slice(0, 2)
return (
<div>
<h2>学生列表数据</h2>
<div className="list">
{
students.filter(item => item.score > 100).slice(0, 2).map(item => {
return (
<div className="item" key={item.id}>
<h2>学号: {item.id}</h2>
<h3>姓名: {item.name}</h3>
<h1>分数: {item.score}</h1>
</div>
)
})
}
</div>
</div>
)
}
}
// 2.创建root并且渲染App组件
const root = ReactDOM.createRoot(document.querySelector("#root"))
root.render(<App/>)
</script>
</body>
</html>
