Disable button - Jquery

Disable the submit button if the file is not chosen.

HTML

<form action="#" method="post">
    <input type="text" name="fileInput" id="fileInput" />
    <input type="submit" value="submit" disabled />
</form>
<div id="result"></div>

JavaScript

$(document).ready(
    function(){
        $('input:file').change(
            function(){
                if ($(this).val()) {
                    $('input:submit').attr('disabled',false); 
                } 
            }
            );
    });