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15.列表渲染.html 1.4 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="UTF-8" />
  5. <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  6. <title>Document</title>
  7. <!-- jsx 语法浏览器不识别 jsx => js 浏览器可识别的语言 -->
  8. <script src="./babel.min.js"></script>
  9. <!-- react的核心库 -->
  10. <script src="./react.development.js"></script>
  11. <!-- 解析react中的dom库 -->
  12. <script src="./react-dom.development.js"></script>
  13. </head>
  14. <body>
  15. <div id="root"></div>
  16. <script type="text/babel">
  17. let root = ReactDOM.createRoot(document.getElementById("root"));
  18. function App() {
  19. return <List />;
  20. }
  21. class List extends React.Component {
  22. constructor() {
  23. super();
  24. this.state = {
  25. list: ["图图", "哆啦A梦", "喜羊羊", "光头强"],
  26. };
  27. }
  28. // 循环:for / while / do while / for in /for of / forEach / map
  29. render() {
  30. // render函数 可以处理所有的js逻辑
  31. const {list} = this.state;
  32. const newsList = list.map((element,index) => <li key={index}>{index+1}-{element}</li>)
  33. return <div>
  34. <ul>
  35. {/* jsx 语法 自动解析 */}
  36. {newsList}
  37. </ul>
  38. </div>;
  39. }
  40. }
  41. root.render(<App />);
  42. </script>
  43. </body>
  44. </html>