在React功能组件中使用useEffect时出错

我正在学习使用React钩子来管理状态，但是我收到一条错误消息：5：3行：在函数“ cockpit”中调用了React Hook“ useEffect”，它既不是React函数的组件也不是自定义的React Hook函数react-hooks /挂钩规则

这是我的代码

import React, {useEffect} from "react";
import classes from "./Cockpit.module.css";

const cockpit = (props) => {
  useEffect(() => {
    console.log('Cockpit js useEffect');

  });

  const assiginedClasses = [];
  let btnClass = "";
  if (props.showPersons) {
    btnClass = classes.Red;
  }

  if (props.persons.length <= 2) {
    assiginedClasses.push(classes.red);
  }

  if (props.persons.length <= 1) {
    assiginedClasses.push(classes.bold);
  }
  return (
    <div className={classes.Cockpit}>
      <h1>Hi I'm a React App</h1>
      <p className={assiginedClasses.join(" ")}>This is really Working!</p>
      <button className={btnClass} onClick={props.clicked}>
        Toggle Name
      </button>
    </div>
  );
};

export default cockpit;