將元素的屬性複製到javascript循環中的其他元素

Question

我在循環js中遇到問題。我想將data-icon的值從.nav類複製到li的#item-control。反正有沒有簡單的方法來解決它與jQuery？

<div id="nav-container"> 
    <ul class="nav"> 
    <li data-icon="images/1.png">Item 1</li> 
    <li data-icon="images/2.png">Item 2</li> 
    <li data-icon="images/3.png">Item 3</li> 
    </ul> 
</div> 

<div id="item-control"> 
    <li>Item Control 1</li> 
    <li>Item Control 2</li> 
    <li>Item Control 3</li> 
</div> 

我已經試過：

$(document).ready(function() { 
    var a = 1; 
    $('#container #nav-container ul.nav li').each(function() { 
     var item_control = $(this).parent().parent().parent().find('#item-control li'); 
     item_control.addClass('item' + a); //this is what I tried before adding data-icon attributes to #item-control li 
     a++; 
    }); 
}); 

Answer 1

var $navItems = $('.nav li'), 
    $itemControlItems = $('#item-control li'); 
$.each($navItems, function(index, el) { 
    $($itemControlItems[index]).data('icon', $(el).data('icon')); 
}); 

Fiddle