Once i need to change shipping address dropdown to div structure.
After a long research i found that this select box is comming form core php file and i do not want to make any change in core file. So at last i changed my shipping.phtml file as following.

I have changed in file
/app/design/frontend/default/[My-Theme]/template/checkout/onepage/shipping.phtml

This code is used for getting the html for select box for presaved address.
I added my new code after this.
<?php echo $this->getAddressesHtmlSelect('shipping') ?>

Now, my code looks like this,


<label for="shipping-address-select"><?php echo $this->__('Select a shipping address from your address book or enter a new address.') ?></label>
<div class="input-box" style="display: none;">
<?php echo $this->getAddressesHtmlSelect('shipping') ?>
</div>
        /*New Code start*/   
<div id="custAddress">
<?php $customerId = Mage::getSingleton('customer/session')->getCustomer();?>    
<?php $customer = Mage::getModel('customer/customer')->load($customerId->getId()); ?>
<?php $data = array();?>
<?php $i=0; foreach ($customer->getAddresses() as $address):?>
<?php $data = $address->toArray();?>
<div id="addresseList">
       <a href="javaScript:void(0);" onclick="setAddress(this.id)" id="<?php echo $i;?>">
       <address> 
          <div id="selected_<?php echo $i;?>" class="selectedImage" style="float: right; margin: -6px; display: none;"><img src="<?php echo $this->getSkinURl()?>images/right.jpg" /></div>
         <?php echo $data['firstname'].' '.$data['lastname'].'<br />';?>
         <?php echo $data['street'].'<br />';?>
         <?php echo $data['city'].','.$data['region'].','.$data['postcode'].'<br />';?>
         <?php $country_name = Mage::app()->getLocale()->getCountryTranslation($data['country_id']);?>
         <?php echo $country_name.'<br />';?>
          <?php echo 'T: '.$data['telephone'];?>
       </address>
    </a>
 </div>
 <?php $i++; endforeach; ?>  
 </div>


<li id="addNewtext"><a href="javaScript:void(0);" onclick="setNewAddress()"><?php echo $this->__('Click to Add new address') ?></a></li>

/*End of New code start*/

I have added javascript and jQuery function in same file at the bottom of the page.

<script type="text/javascript">
function setAddress(obj)
{
    document.getElementById('shipping-address-select').selectedIndex = obj;
    jQuery(".selectedImage").hide();
    jQuery("#selected_"+obj).show();
    jQuery("#shipping-new-address-form").hide();
    jQuery("#addNewtext").show();
}
function setNewAddress()
{
    jQuery("#shipping-address-select").find("option:contains('New Address')").each(function()
    {
     if( jQuery(this).text() == 'New Address' )
     {
        jQuery(this).attr("selected","selected");
        jQuery("#shipping-new-address-form").show();
        jQuery("#addNewtext").hide();
        jQuery(".selectedImage").hide();
      }
    });
}
</script>  


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