Magento – the variable that holds the My Cart url

1. There is no specific event triggered for abandoned cart (as far as I know).
2. You can check it manually using a cron job.
3. You can use controller_action_postdispatch_customer_account_logout event to check the sales_flat_quote table which aren't present in sales_flat_order table. This will give you the abandoned quotes (in other words abandoned carts).

this link will give you the exact answer for your question.

note:

You cannot rely on controller_action_postdispatch_customer_account_logout event completely as there are many untraceable instances, which will result in abandoned carts viz.

• User closing browser window
• Sudden power off etc.

Therefore cron would be the better Idea!

or

There are some paid extensions to do this job for you.

• http://www.magentocommerce.com/magento-connect/Adjustware/extension/1290/abandoned-carts-alerts-pro
• http://www.extendware.com/abandoned-cart-reminder-magento-extension.html

I also posted this question in stackoverflow and it was resolved using this solution.

function startsWith($haystack, $needle)
{
    return $needle === "" || strpos($haystack, $needle) === 0;
}

$currentUrl = Mage::helper('core/url')->getCurrentUrl();
$url = Mage::getSingleton('core/url')->parseUrl($currentUrl);
$path = $url->getPath();
if (startsWith($path, '/blog/') || (strcmp($path, '/blog') == 0))
{
    //Do something on /blog and all pages underneath
}

This are for those who are having the same problem like me. :D

SOURCE: https://stackoverflow.com/questions/25297270/show-something-in-a-subpage-and-all-pages-under-that-subpage-in-php/25298390#25298390