React官网学习实践 - 列表 & Keys

渲染多样的组件

const numbers = [1, 2, 3, 4, 5];
const listItems = numbers.map((number) =>
  <li>{number}</li>
);

ReactDOM.render(
  <ul>{listItems}</ul>,
  document.getElementById('root')
);

基础列表组件

render() {
        const numbers = [1,6,8];
        const listItems = numbers.map((number) =>
            <li>{number}</li>
        );
    return (
        <div>
            <ul>{listItems}</ul>
        </div>
    );
  }

Key的使用, 都挺符合ES6的对象的使用，也没什么好测试的了。定义一个对象，里面包含三个字段，选某一字段作为key,保证其唯一性即可。

function Blog(props) {
  const sidebar = (
    <ul>
      {props.posts.map((post) =>
        <li key={post.id}>
          {post.title}
        </li>
      )}
    </ul>
  );
  const content = props.posts.map((post) =>
    <div key={post.id}>
      <h3>{post.title}</h3>
      <p>{post.content}</p>
    </div>
  );
  return (
    <div>
      {sidebar}
      <hr />
      {content}
    </div>
  );
}

const posts = [
  {id: 1, title: 'Hello World', content: 'Welcome to learning React!'},
  {id: 2, title: 'Installation', content: 'You can install React from npm.'}
];
ReactDOM.render(
  <Blog posts={posts} />,
  document.getElementById('root')
);