Introduction to Zend\Config

Zend\Config is designed to simplify access to 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 that read and write configuration data stored in .ini, JSON, YAML and XML files.

Using Zend\Config\Config with a Reader Class

Normally, it is expected that users would use one of the reader classes to read a configuration file, but if configuration data are available in a PHP array, one may simply pass the data to Zend\Config\Config’s constructor in order to utilize a simple object-oriented interface:

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// An array of configuration data is given
$configArray = array(
    'webhost'  => '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 using the configuration data
$config = new Zend\Config\Config($configArray);

// Print a configuration datum (results in 'www.example.com')
echo $config->webhost;

As illustrated in the example above, Zend\Config\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\Config also has get() method that returns the supplied value if the data element doesn’t exist in the configuration array. For example:

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$host = $config->database->get('host', 'localhost');

Using Zend\Config\Config with a PHP Configuration File

It is often desirable to use a purely PHP-based configuration file. The following code illustrates how easily this can be accomplished:

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// config.php
return array(
    'webhost'  => 'www.example.com',
    'database' => array(
        'adapter' => 'pdo_mysql',
        'params'  => array(
            'host'     => 'db.example.com',
            'username' => 'dbuser',
            'password' => 'secret',
            'dbname'   => 'mydatabase'
        )
    )
);
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// Consumes the configuration array
$config = new Zend\Config\Config(include 'config.php');

// Print a configuration datum (results in 'www.example.com')
echo $config->webhost;