封装hook

• 封装个函数，使用hook语法, 导出一个函数

import React, { useState, useEffect } from 'react';
const useKeyPress = (targetKeyCode) => {
  const [keyPressed, setKeyPressed] = useState(false)
  const keyDownHandler = ({keyCode}) => {
    if (keyCode === targetKeyCode) {
      setKeyPressed(true)
    }
  }
  const keyUpHandler = ({keyCode}) => {
    if (keyCode === targetKeyCode) {
      setKeyPressed(false)
    }
  }
  useEffect(() => {
    document.addEventListener('keydown', keyDownHandler)
    document.addEventListener('keyup', keyUpHandler)
    return () => {
      document.removeEventListener('keydown', keyDownHandler)
      document.removeEventListener('keyup', keyUpHandler)
    }
  // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []) // 只在第一次加载触发
  return keyPressed
}
export default useKeyPress