JSFiddle - React, Tailwind, and code Playground

HTML

<p><input type="text" name="name" id="proname" value="" /></p>  
<p><input type="text" name="var" id="provarname" value="" /></p>

JavaScript

$(document).ready(function() {
    $('#proname').live('keyup',function() {
        var pronameval = $(this).val();
        $('#provarname').val(pronameval.replace(/ /g, '-').toLowerCase());
    });
});