React 中的 useState() 是什么？

我目前正在学习 React 中的钩子概念并试图理解下面的示例。

import { useState } from 'react';function Example() {    // Declare a new state variable, which we'll call "count"    const [count, setCount] = useState(0);  return (    <div>      <p>You clicked {count} times</p>      <button onClick={() => setCount(count + 1)}>        Click me      </button>    </div>  );}

上面的例子增加了处理函数参数本身的计数器。如果我想在事件处理函数中修改计数值怎么办

考虑下面的例子：

setCount = () => {  //how can I modify count value here. Not sure if I can use setState to modify its value  //also I want to modify other state values as well here. How can I do that}<button onClick={() => setCount()}>  Click me</button>