JSFiddle - React, Tailwind, and code Playground

HTML

<input type='text' />
<span></span>

JavaScript

$('input').keypress(function(e) {
    var a = [];
    var k = e.which;
    
    for (i = 48; i < 58; i++)
        a.push(i);
    
    if (!(a.indexOf(k)>=0))
        e.preventDefault();
    
    $('span').text('KeyCode: '+k);
});