FEM btholt: useEffect hook example (Intermediate React v2)

useEffect-example.js

import React, { useState, useEffect } from "react";

// Count useEffect calls (cumulative)
let ticks = 0;

const EffectComponent = () => {
  const [time, setTime] = useState(new Date());

  useEffect(() => {
    console.log(++ticks); // Log count @ each call
    // Move state update into anonymous function for setTimeout()
    const timer = setTimeout(() => setTime(new Date()), 1000);
    return () => clearTimeout(timer);
  });

  return <h1>useEffect Example: {time.toLocaleTimeString()}</h1>;
};

export default EffectComponent;