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 (!($.inArray(k,a)>=0))
            e.preventDefault();
    });