Question

I know I can select an option in a select box by doing

$('#selectBox :nth-child(4)').attr('selected', 'selected');

But how can I do this through a returned jQuery object? e.g. something like

var box = $('#selectBox');
$(box  :nth-child(4)').attr('selected', 'selected');

Answer 1

You can use children:

box.children(':nth-child(4)').attr('selected', 'selected');

BTW, starting from jQuery 1.6 you can use prop instead of attr:

box.children(':nth-child(4)').prop('selected', true);