Question

Why i always get a value(bu0) of typing in 3 field different(class="bg_units bu0", class="bg_units bu1", class="bg_units bu2") ?

I want if user typing value in field bu0 get dynamic part 2 class="bg_units bu0" of class (.bu0), as for other:

• if typing each value on field bu0 =get class=> .bu0
• if typing each value on field bu1 =get class=> .bu1
• if typing each value on field bu2 =get class=> .bu2

EXAMPLE: http://jsfiddle.net/jJaYT/

$('.eghamat').live('keyup',function () {
    var $this = $(this),
    $div = $this.closest('div.find_input'),
    bu_num =  '.' + $div.find('.bg_units').attr('class').split(" ")[1];
    alert(bu_num);
});

Answer 1

Your code should do this:

$('.eghamat').live('keyup', function() {
    var $this = $(this),
        $div = $this.closest('div.bg_units'),
        bu_num = '.' + $div.attr('class').split(" ")[1];
    alert(bu_num);
});

You are going up to the topmost div, which contains everything, searching for .bg_units and always getting the first one. Just call $this.closest('div.bg_units'),