JSFiddle - React, Tailwind, and code Playground

by nottrobin

HTML

<form name="numberForm">
<input type="number" name="number" />
<button type="submit">submit</button>
</form>

JavaScript

// NB: jQuery is required
jQuery('[name="numberForm"]').bind(
    'submit',
    function(evt) {
        if(jQuery('[name="number"]').val() % 20 != 0) {
            alert('Your number is wrong');
            evt.preventDefault();
        }
    }
);