Question

I have troubles to get the parent id of elements.

$(function(){
$("#elem-132224").append("<button class='sum'>+</button><button>-</button>")
$(".sum").click(function(){
    alert($(this).attr('id'));
})

why is not working?

Answer 1

It doesn’t work because the button doesn’t have an id. It merely has class. You can write it like this:

$(function(){
  $("#elem-132224").append("<button id='my-id-123' class='sum'>+</button><button>-</button>");
  $(".sum").click(function(){
    alert($(this).attr('id'));
});

If you want to get the parent id (the element which <button> is inside it), you can use parent() in jquery:

$(function(){
  $("#elem-132224").append("<button class='sum'>+</button><button>-</button>");
  $(".sum").click(function(){
    alert($(this).parent().attr('id'));
});