JSFiddle - React, Tailwind, and code Playground

HTML

<button id="btnHello1" type=button>안녕1</button>
<button id="btnHello2" type=button>안녕2</button>
<button id="btnHello3" type=button>안녕3</button>

JavaScript

var btnEle1 = document.getElementById('btnHello1');
var btnEle2 = document.getElementById('btnHello2');
var btnEle3 = document.getElementById('btnHello3');

function helloAlert() {
  var text = this.textContent;
  alert(text);
}

btnEle1.addEventListener('click', helloAlert);
btnEle2.addEventListener('click', helloAlert);
btnEle3.addEventListener('click', helloAlert);