IntroductionZend_Config is designed to simplify the access to, and the use of,
configuration data within applications. It provides a nested object property based user
interface for accessing this configuration data within application code. The configuration
data may come from a variety of media supporting hierarchical data storage. Currently
Zend_Config provides adapters for configuration data that are stored
in text files with Zend_Config_Ini and
Zend_Config_Xml.
Using Zend_Config
Normally it is expected that users would use one of the adapter classes such as Zend_Config_Ini or
Zend_Config_Xml,
but if configuration data are available in a PHP array, one may
simply pass the data to the Zend_Config constructor in order to
utilize a simple object-oriented interface:
'www.example.com',
'database' => array(
'adapter' => 'pdo_mysql',
'params' => array(
'host' => 'db.example.com',
'username' => 'dbuser',
'password' => 'secret',
'dbname' => 'mydatabase'
)
)
);
// Create the object-oriented wrapper upon the configuration data
$config = new Zend_Config($configArray);
// Print a configuration datum (results in 'www.example.com')
echo $config->webhost;
// Use the configuration data to connect to the database
$db = Zend_Db::factory($config->database->adapter,
$config->database->params->toArray());
// Alternative usage: simply pass the Zend_Config object.
// The Zend_Db factory knows how to interpret it.
$db = Zend_Db::factory($config->database);
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As illustrated in the example above, Zend_Config provides nested
object property syntax to access configuration data passed to its constructor.
Along with the object oriented access to the data values,
Zend_Config also has get() which will
return the supplied default value if the data element doesn't exist. For example:
database->get('host', 'localhost');
]]>Using Zend_Config with a PHP Configuration File
It is often desirable to use a pure PHP-based configuration file.
The following code illustrates how easily this can be accomplished:
'www.example.com',
'database' => array(
'adapter' => 'pdo_mysql',
'params' => array(
'host' => 'db.example.com',
'username' => 'dbuser',
'password' => 'secret',
'dbname' => 'mydatabase'
)
)
);
]]>webhost;
]]>