Mryntu

I want to add active class in top links?

appdesignfrontenddefaultdefaulttemplatepagetemplatelinks.phtml

<?php $_links = $this->getLinks(); ?>
<?php if (count($_links) > 0): ?>
 <ul class="links"<?php if ($this->getName()): ?> id="<?php echo $this->getName() ?>"<?php endif; ?>>
 <?php foreach ($_links as $_link): ?>
 <?php if ($_link instanceof Mage_Core_Block_Abstract): ?>
 <?php echo $_link->toHtml() ?>
 <?php else: ?>
 <li<?php if ($_link->getIsFirst() || $_link->getIsLast()): ?> class="<?php if ($_link->getIsFirst()): ?>first<?php endif; ?><?php if ($_link->getIsLast()): ?> last<?php endif; ?>"<?php endif; ?> <?php echo $_link->getLiParams() ?>><?php echo $_link->getBeforeText() ?><a href="<?php echo $_link->getUrl() ?>" title="<?php echo $_link->getTitle() ?>" <?php echo $_link->getAParams() ?>><?php echo $_link->getLabel() ?></a><?php echo $_link->getAfterText() ?></li>
 <?php endif; ?>
 <?php endforeach; ?>
 </ul>
<?php endif; ?>

what about:

<?php $_links = $this->getLinks(); ?>
<?php 
// active states
// using $_link->getBeforeText() against the RouteName or Idenifier ti get active states
$routeName = Mage::app()->getRequest()->getRouteName();
$identifier = Mage::getSingleton('cms/page')->getIdentifier();
if ($identifier ==null): 
$identifier = $routeName; 
endif;
?>
<?php if(count($_links)>0): ?>
<ul class="links"<?php if($this->getName()): ?> id="<?php echo $this->getName() ?>"<?php endif;?>>
 <?php foreach($_links as $_link): ?>
 <?php if ($_link instanceof Mage_Core_Block_Abstract):?>
 <?php echo $_link->toHtml() ?>
 <?php else: ?>
 <li class="<?php echo $_link->getBeforeText(); if( $identifier == $_link->getBeforeText()): echo " active"; endif; ?> <?php if($_link->getIsFirst()||$_link->getIsLast()): ?><?php if($_link->getIsFirst()): ?>first<?php endif; ?><?php if($_link->getIsLast()): ?> last<?php endif; ?><?php endif; ?>" <?php echo $_link->getLiParams() ?>><?php // echo $_link->getBeforeText() ?><a href="<?php echo $_link->getUrl() ?>" title="<?php echo $_link->getTitle() ?>" <?php echo $_link->getAParams() ?>><?php echo $_link->getLabel() ?></a><?php echo $_link->getAfterText() ?></li>
 <?php endif;?>
 <?php endforeach; ?>
</ul>

<?php endif; ?>

A better and more cleaner and also simple approach would be to compare every link's url with the current url and if matches then add "active" class to it.

<?php $_links = $this->getLinks(); ?>
<?php $currentUrl = Mage::helper('core/url')->getCurrentUrl(); ?>

<?php if (count($_links) > 0): ?>
 <ul class="links"<?php if ($this->getName()): ?> id="<?php echo $this->getName() ?>"<?php endif; ?>>
 <?php foreach ($_links as $_link): ?>
 <?php if ($_link instanceof Mage_Core_Block_Abstract): ?>
 <?php echo $_link->toHtml() ?>
 <?php else: ?>
 <li<?php if ($_link->getIsFirst() || $_link->getIsLast()): ?> class="<?php if ($_link->getIsFirst()): ?>first<?php endif; ?><?php if ($_link->getIsLast()): ?> last<?php endif; ?><?php if($_link->getUrl() == $currentUrl): ?> active<?php endif; ?>"<?php endif; ?> <?php echo $_link->getLiParams() ?>><?php echo $_link->getBeforeText() ?><a href="<?php echo $_link->getUrl() ?>" title="<?php echo $_link->getTitle() ?>" <?php echo $_link->getAParams() ?>><?php echo $_link->getLabel() ?></a><?php echo $_link->getAfterText() ?></li>
 <?php endif; ?>
 <?php endforeach; ?>
 </ul>
<?php endif; ?>

But the urls if same shouldn't have even the difference of last slash or this condition won't work, so you might want to use rtrim($url, '/'); for removing last trailing slash.

Hope this helps.