JSFiddle - React, Tailwind, and code Playground
HTML
<div>
<select>
<option></option>
<option>Hi</option>
<option>Mi</option>
</select>
</div>
<button>
asdasdas
</button>
JavaScript
$(function() {
/* $("select").attr("multiple", true) */;
});
$("button").on("click", function(){
alert($("select").val());
});