How to wrap multiple div blocks with different cla

Possible Duplicate:
How to wrap DIV tags with different class names in jQuery?

I have the following HTML blocks repeated in the document

<!-- first block -->
<div class="first">
   My first div
</div>
<div class="second">
   My second div
</div>

<!-- second block -->
<div class="first">
   My first div
</div>
<div class="second">
   My second div
</div>

...

How can I wrap the blocks of Divs with jQuery to get the following result...

<!-- first block -->
<div class="container">
   <div class="first">
      My first div
   </div>    
   <div class="second">
      My second div
   </div>
</div>

<!-- second block -->
<div class="container">
   <div class="first">
      My first div
   </div>    
   <div class="second">
      My second div
   </div>
</div>

...

You can do something like this :

$('#btnTest').on('click', function() {
    $("body").append('<div class="container"></div>');
    $("body").append('<div class="container"></div>');

    $(".first").eq(0)
        .clone()
            .appendTo($(".container").eq(0))
            .end()
        .remove();

    $(".second").eq(0)
        .clone()
            .appendTo($(".container").eq(0))
            .end()
        .remove();

    $(".first").eq(0)
        .clone()
            .appendTo($(".container").eq(1))
            .end()
        .remove();

    $(".second").eq(0)
        .clone()
            .appendTo($(".container").eq(1))
            .end()
        .remove();
});

First you add to the DOM the number of div you want with class container. Then for each div .first and .second you have to take the first in the dom $(".first").eq(0) clone it, then append it to the first ".container". You have to use .end() before remove to make sure to remove the original div and not the cloned one.

You do this for each div and you change the ".container" by changing the number in $(".container").eq(0).

This code works fine for your example, but if you have more ".container" you should make a loop of it.