<div class="tr">click clone</div>
<select name="ItemToOrders[0][Qty]" id="s1" class="aa">
<option value="tt">tt</option>
<option value="tr">tr</option>
<option value="ty">ty</option>
</select>
<div class="trq"> </div>$('body').on('change', 'select', function(){
$('option', $(this)).removeAttr('selected');
$('option:selected', $(this)).attr('selected', 'selected');
});
$(".tr").click(function () {
var s = $(".aa").length;
let $self = $(".aa").last();
let name = $self.attr('name');
let newName = name.replace(/(.*?\[)\d+(\].*)/i, '$1' + s + '$2');
$self.attr('name', newName);
$self.clone().attr('name', newName).appendTo('.trq');
});
External CSS
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