从App.js控制组件状态并更改它们的值

import React, { useState } from "react";

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

  // 其他组件的渲染和交互逻辑

  return (
    <div>
      <h1>当前计数：{count}</h1>
      <button onClick={() => setCount(count + 1)}>增加</button>
    </div>
  );
}

export default App;

import React from "react";

function ChildComponent(props) {
  const { count } = props;

  return (
    <div>
      <h2>子组件</h2>
      {count > 0 ? <p>Count大于0</p> : <p>Count小于等于0</p>}
    </div>
  );
}

export default ChildComponent;

import React, { useState } from "react";
import ChildComponent from "./ChildComponent";

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

  return (
    <div>
      <h1>当前计数：{count}</h1>
      <button onClick={() => setCount(count + 1)}>增加</button>
      <ChildComponent count={count} />
    </div>
  );
}

export default App;