无法在卸载的组件#434上执行React状态更新

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

function MyComponent() {
  const [count, setCount] = useState(0);

  useEffect(() => {
    const timer = setTimeout(() => {
      setCount(count + 1);
    }, 1000);

    return () => {
      clearTimeout(timer); // 清除定时器，防止组件卸载后更新状态
    };
  }, [count]);

  return (
    <div>
      <p>Count: {count}</p>
    </div>
  );
}

export default MyComponent;

import React, { Component } from 'react';

class MyComponent extends Component {
  constructor(props) {
    super(props);
    this.state = {
      count: 0,
    };
    this.isMounted = false;
  }

  componentDidMount() {
    this.isMounted = true;
    this.timer = setTimeout(() => {
      if (this.isMounted) {
        this.setState({ count: this.state.count + 1 });
      }
    }, 1000);
  }

  componentWillUnmount() {
    this.isMounted = false;
    clearTimeout(this.timer);
  }

  render() {
    return (
      <div>
        <p>Count: {this.state.count}</p>
      </div>
    );
  }
}

export default MyComponent;