const {useContext} = React
const Context = React.createContext()

function Provider(props) {
  return (
    <Context.Provider value={{data: "haha"}}>
      {props.children}
    </Context.Provider>
  )
}

function Children() {
  const {data} = useContext(Context)
  return (
    <div>Children获取到的数据{data}</div>
  )
}

ReactDOM.render(<Provider><Children /></Provider>, document.getElementById("root"))