JSFiddle - React, Tailwind, and code Playground

HTML

<form action="" method="GET">
<fieldset>
    <input type="text" name="name" value="">
    <input type="submit" value="OK">
</fieldset>
</form>

JavaScript

document.forms[0].onsubmit = function () {
    alert("Submit");
    return false;
};

// elements[0] = fieldset
// elements[1] = text
// elements[2] = submit
document.forms[0].elements[2].onclick = function () {
    alert("Click");
    return false;
};