useEffect、useCallback、useMemo的依赖数组

Question

我对 React Hooks 的依赖性很困惑。这是示例：

const memorizeValue = useMemo(() => {
    return {
      count,
      setCount,
    }
  }, [count, setCount])

在 React 纪录片中：

Note

The array of dependencies is not passed as arguments to the function. Conceptually, though, that’s what they represent: every value referenced inside the function should also appear in the dependencies array. In the future, a sufficiently advanced compiler could create this array automatically.

count 和 setCount 都在 useMemo 的回调中，如果我没有在依赖数组中传递 setCount，eslint 不会警告我，但是 count 会，所以有什么区别？为什么不需要传递 setCount？ setCount 在 useMemo 里面，不是吗？

这是代码框 link:

https://codesandbox.io/s/react-codesandbox-forked-xfupk?file=/src/Demo1/index.js:254-363

我想我可能误解了文档。有人指出，谢谢。

Answer 1

勾选useState docs

Note

React guarantees that setState function identity is stable and won’t change on re-renders. This is why it’s safe to omit from the useEffect or useCallback dependency list.

假设 setCount 是 useState 钩子的更新函数，那么它保证是一个稳定的引用。

useEffect、useCallback、useMemo的依赖数组

The dependency array of useEffect, useCallback, useMemo

reactjs

react-hooks

use-state

usecallback

react-usememo