React에서 State 사용하는 법

Counter.js

import React, { useState } from 'react';

const Counter = () => {
    const [number, setNumber] = useState(0);
    
    handleIncrease = () => {
        setNumber(number + 1);   
    };
    
    handlerDecrease = () => {
        setNumber(number - 1);  
    };

    return (
        <div>
            <h1>counter</h1>
            <p>{number}</p>
            <button onClick={handleIncrease}>+</button>
            <button onClick={handleDecrease}>-</button>
        </div>
    )
}

export default Counter;