JSFiddle - React, Tailwind, and code Playground

by eorozco

HTML

<select name="test" multiple>
    <option value="1">Uno</option>
    <option value="2">Dos</option>
    <option value="3">Tres</option>
    <option value="4">Cuatro</option>
</select>

<div id="log"></div>

JavaScript

(function () {
    var previo;

    $("select[name=test]").focus(function () {
        
        previo = $(this).val();
        
    }).change(function() {
        var actual = $(this).val();
        document.getElementById("log").innerHTML = "<b>Previo: </b>"+previo;
        document.getElementById("log").innerHTML += "<br><b>Actual: </b>"+actual;
        
        previo = $(this).val();
    });
})();