JSFiddle - React, Tailwind, and code Playground

by Derek Leung

HTML

<span id="displayDiv"></span><button>Go</button>

JavaScript

function countDown(i, callback) {
    callback = callback || function(){};
    var int = setInterval(function() {
        document.getElementById("displayDiv").innerHTML = "Number: " + i;
        i-- || (clearInterval(int), callback());
    }, 1000);
}
$("button").click(function(){
    countDown(5, function(){
        alert("Countdown done!")
    });
});