jquery - Check if all checkboxes are selected

Question

How do I check if all checkboxes with class="abc" are selected?

I need to check it every time one of them is checked or unchecked. Do I do it on click or change?

Answer 1

I think the easiest way is checking for this condition:

$('.abc:checked').length == $('.abc').length

You could do it every time a new checkbox is checked:

$(".abc").change(function(){
    if ($('.abc:checked').length == $('.abc').length) {
       //do something
    }
});