How to get logged in customer's details by customer's id in Magento

If you want to display customer's details by customer's id in Magento. 

You can use following code:

<?php

  // Check if any customer is logged in or not
if (Mage::getSingleton('customer/session')->isLoggedIn())
{

// Load the customer's data
$customer = Mage::getSingleton('customer/session')->getCustomer();

$id =$customer->getId(); // To get Customer Id

//Get Details Using Customer Id
$customer = Mage::getModel('customer/customer')->load($id)->getData();

                $customer->getName();                  

               $customer->getEmail();

}
?>

How to get logged in customer's details in Magento

If you want to get logged in customer's details in Magento. 

You can use following code:

<?php

  // Check if any customer is logged in or not
if (Mage::getSingleton('customer/session')->isLoggedIn())
{

// Load the customer's data
$customer = Mage::getSingleton('customer/session')->getCustomer();

$customer->getPrefix();
$customer->getName();                    // Full Name
$customer->getFirstname();            // First Name
$customer->getMiddlename();       // Middle Name
$customer->getLastname();           // Last Name
$customer->getSuffix();

// All other customer data
$customer->getWebsiteId();
$customer->getEntityId();
$customer->getEntityTypeId();
$customer->getAttributeSetId();
$customer->getEmail();
$customer->getGroupId();
$customer->getStoreId();
$customer->getCreatedAt();
$customer->getUpdatedAt();
$customer->getIsActive();
$customer->getDisableAutoGroupChange();
$customer->getTaxvat();
$customer->getPasswordHash();
$customer->getCreatedIn();
$customer->getGender();
$customer->getDefaultBilling();
$customer->getDefaultShipping();
$customer->getDob();
$customer->getTaxClassId();
}
?>

How to get customer name, customer email on order success page in Magento

If you want to display customer name and email on order success page in Magento. 

So use following code on success.phtml page 

(/public_html/app/design/frontend/base/default/template/checkout/success.phtml)

<?php

 $order = Mage::getModel('sales/order')->loadByIncrementId($this->getOrderId());

      echo $order->getCustomerName();

      echo $order->getCustomerEmail();

?>

How to get custom attribute value in Magento

Display custom attribute value in Magento

When we get custom attribute value in Magento through simple way like:

<?php 

echo $_product->getAttributeText('custom_attribute_code');

?>

Then we will get a fatal error (as following) , if the custom attribute is not already added. 

" Fatal error: Call to a member function getSource() on a non-object in ...\app\code\core\Mage\Catalog\Model\Product.php on line 1388"

So we will use following code for get custom attribute value in Magento.

The following code will first check that the custom attribute are added or not in admin. If custom attribute are added then get its value.

<?php 

$attribute = $_product->getResource()->getAttribute('custom_attribute_code');

         if ($attribute)

          {

               echo $attribute_value = $attribute ->getFrontend()->getValue($_product);

          }

?>