JSFiddle - React, Tailwind, and code Playground

HTML

<select id="mySelect">
        <option value="1">test1</option>
        <option value="2">test2</option>
        <option value="3">test3</option>
    <option value="">no value defined</option>
    </select>
<div id="display"></div>

CSS

div{
    margin: 20px 0px;
}

JavaScript

var e = document.getElementById('mySelect');
var d =  document.getElementById('display');
e.onchange = function(){
    d.innerHTML = [
        e.value,
        e.options[e.selectedIndex].text,
        e.options[e.selectedIndex].value
        ].join(' ');
};