如何将ref放入props.children

// 父组件
class ParentComponent extends React.Component {
  componentDidMount() {
    // 通过this.childRef可以访问到子组件的实例或DOM元素
    console.log(this.childRef);
  }

  render() {
    return (
      <div>
        {React.Children.map(this.props.children, child => {
          if (child && child.props.ref) {
            // 将ref函数或对象传递给子组件的ref属性
            return React.cloneElement(child, {
              ref: this.childRef
            });
          }
          return child;
        })}
      </div>
    );
  }
}

// 子组件
class ChildComponent extends React.Component {
  render() {
    return <div ref={this.props.ref}>Hello, World!</div>;
  }
}

// 使用例子
class Example extends React.Component {
  constructor(props) {
    super(props);
    this.childRef = React.createRef();
  }

  render() {
    return (
      <ParentComponent>
        <ChildComponent ref={this.childRef} />
      </ParentComponent>
    );
  }
}