JSFiddle - React, Tailwind, and code Playground

HTML

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

<br />
<a href="#" id="validate">validate</a>

JavaScript

function Validate(name){    
    re = /^[A-Za-z]+$/;
    if(re.test(name))
    {
       alert('Valid Name.');
    }
    else
    {
       alert('Invalid Name.');

    }
}
$(function(){
    $("#validate").click(function(){
        var val = $('#input').val();
        Validate(val)}
);
});