在react本机中获取元素

class MyComponent extends React.Component {
  constructor(props) {
    super(props);
    this.myRef = React.createRef();
  }

  componentDidMount() {
    console.log(this.myRef.current); // 访问元素的DOM节点
  }

  render() {
    return <div ref={this.myRef}>Hello, World!</div>;
  }
}

class MyComponent extends React.Component {
  componentDidMount() {
    console.log(this.myRef); // 访问元素的DOM节点
  }

  render() {
    return <div ref={node => this.myRef = node}>Hello, World!</div>;
  }
}

import React, { useRef, useEffect } from 'react';

function MyComponent() {
  const myRef = useRef(null);

  useEffect(() => {
    console.log(myRef.current); // 访问元素的DOM节点
  }, []);

  return <div ref={myRef}>Hello, World!</div>;
}