JSFiddle - React, Tailwind, and code Playground

HTML

<select name="test">
    <option>One</option>
    <option>Two</option>
</select>
<select name="test2">
    <option>One</option>
    <option>Two</option>
</select>

JavaScript

var selects = document.getElementsByTagName('select');

for(var i in selects)
{
    selects[i].onchange = function changeWeek(e) {console.log(e.target.name);}
}