jQuery - Detect value change which use .val() function

Question

We all know that use the val() will not trigger the change event, so we also use .trigger('change') behind the val().

But the problem is that someone write the val() did't with trigger() and it's a external file that I can't edit it.

So, how can I detect value change through some code same like below:

$('.elem').on('change', function(){
   // do something
});

Answer 1

My suggestion is to override jquery's val()

var originalValFn = jQuery.fn.val;

jQuery.fn.val = function() {
    this.trigger('change');
    originalValFn.apply( this, arguments );
}

jsfiddle: http://jsfiddle.net/2L7hohjz/js