DateTime.js

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

export const DateTime = () => {
  var [date, setDate] = useState(new Date());

  useEffect(() => {
    var timer = setInterval(() => setDate(new Date()), 1000);
    return function cleanup() {
      clearInterval(timer);
    }
  })

  return (
        <div>
            Time : {date.toLocaleTimeString()}      
            Date : {date.toLocaleDateString()}
        </div>
  )
}

export default DateTime;