The first time an instance of the autoloader is retrieved, it
registers itself with spl_autoload. You retrieve an
instance using the getInstance() method:
<?php
$autoloader = Zend_Loader_Autoloader::getInstance();
By default, the autoloader is configured to match the "Zend_" and
"ZendX_" namespaces. If you have your own library code that uses
your own namespace, you may register it with the autoloader using
the registerNamespace() method. For instance, if your
library code is prefixed with "My_", you could do so as follows:
<?php
$autoloader->registerNamespace('My_');
Namespace Prefixes
You'll note that the previous example uses "My_" and not "My".
This is because Zend_Loader_Autoloader is intended
as a general purpose autoloader, and does not make the
assumption that a given class prefix namespace includes an
underscore. If your class namespace does
include one, you should include it when registering your
namespace.
You can also register arbitrary autoloader callbacks, optionally
with a specific namespace (or group of namespaces).
Zend_Loader_Autoloader will attempt to match these
first before using its internal autoloading mechanism.
As an example, you may want to utilize one or more eZcomponents
components with your Zend Framework application. To use its
autoloading capabilities, push it onto the autoloader stack using
pushAutoloader():
<?php
$autoloader->pushAutoloader(array('ezcBase', 'autoload'), 'ezc');
This tells the autoloader to use the eZcomponents autoloader for classes beginning with "ezc".
You can use the unshiftAutoloader() method to add the
autoloader to the beginning of the autoloader chain.
By default, Zend_Loader_Autoloader does no error
suppression when using its internal autoloader, which utilizes
Zend_Loader::loadClass(). Most of the time, this is
exactly what you want. However, there may be cases where you want to
suppress them. You can do this using
suppressNotFoundWarnings():
<?php
$autoloader->suppressNotFoundWarnings(true);
Finally, there may be times when you want the autoloader to load any
namespace. For instance, PEAR libraries do not share a common
namespace, making specifying individual namespaces difficult when
many PEAR components are in use. You can use the
setFallbackAutoloader() method to have the autoloader
act as a catch-all:
<?php
$autoloader->setFallbackAutoloader(true);
Loading Classes from PHP Namespaces
Starting in version 1.10.0, Zend Framework now allows loading classes from PHP namespaces. This support follows the same guidelines and implementation as that found in the PHP Framework Interop Group PSR-0 reference implementation.
Under this guideline, the following rules apply:
Each namespace separator is converted to a
DIRECTORY_SEPARATORwhen loading from the file system.Each "_" character in the CLASS NAME is converted to a
DIRECTORY_SEPARATOR. The "_" character has no special meaning in the namespace.The fully-qualified namespace and class is suffixed with ".php" when loading from the file system.
As examples:
\Doctrine\Common\IsolatedClassLoader=>/path/to/project/lib/vendor/Doctrine/Common/IsolatedClassLoader.php\namespace\package\Class_Name=>/path/to/project/lib/vendor/namespace/package/Class/Name.php\namespace\package_name\Class_Name=>/path/to/project/lib/vendor/namespace/package_name/Class/Name.php