jQuery disable/enable submit button

Question

I have this HTML:

How can I do something li

Answer 1

The problem is that the change event fires only when focus is moved away from the input (e.g. someone clicks off the input or tabs out of it). Try using keyup instead:

$(document).ready(function() {
     $(':input[type="submit"]').prop('disabled', true);
     $('input[type="text"]').keyup(function() {
        if($(this).val() != '') {
           $(':input[type="submit"]').prop('disabled', false);
        }
     });
 });