useContext 在子组件中返回未定义

Question

I'm learning hooks and trying to understand useContext . The component is a child of the provider ,

But when I see the value returned by useContext , it is undefined .

https://codesandbox.io/s/divine-star-2mz87?file=/src/C2.js

In the component C2, I get undefined

Answer 1

you should use named import in c2:

import {CContext} from "./App";

instead of default import which will give you App react component import CContext from "./App";