从props更新useState

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

function ChildComponent(props) {
  const [count, setCount] = useState(props.initialCount);

  useEffect(() => {
    setCount(props.initialCount);
  }, [props.initialCount]);

  return (
    <div>
      <p>Count: {count}</p>
      <button onClick={() => setCount(count + 1)}>Increment</button>
    </div>
  );
}

function ParentComponent() {
  const [initialCount, setInitialCount] = useState(0);

  return (
    <div>
      <ChildComponent initialCount={initialCount} />
      <button onClick={() => setInitialCount(initialCount + 1)}>Update Props</button>
    </div>
  );
}