jquery live event for added dom elements

Question

I want to add a class to any DOM element that is on the page now or in the future that has a specified class and meets some criteria

so for some pseudo code

Answer 1

You can't do this.

You'll have to do:

$('.location').filter(function () {
    return ($(this).find('input:first').val().substr(0, 1) == "!");
}).addClass('hidden');

To apply it to all currently elements on the page, and then manually add the 'hidden' class to future elements you add to the DOM.