DependencyInjection Component

DependencyInjection manages your services via a robust and flexible Dependency Injection Container.

Here is a simple example that shows how to register services and parameters:

use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\Reference;
$sc = new ContainerBuilder();
$sc
->register('foo', '%foo.class%')
->addArgument(new Reference('bar'))
;
$sc->setParameter('foo.class', 'Foo');
$sc->get('foo');

Resources

You can run the unit tests with the following command:

phpunit -c src/Symfony/Component/DependencyInjection/

If you also want to run the unit tests that depend on other Symfony Components, declare the following environment variables before running PHPUnit:

export SYMFONY_CONFIG=../path/to/Config
export SYMFONY_YAML=../path/to/Yaml

More Examples

Method Calls (Setter Injection):

$sc = new ContainerBuilder();
$sc
->register('bar', '%bar.class%')
->addMethodCall('setFoo', array(new Reference('foo')))
;
$sc->setParameter('bar.class', 'Bar');
$sc->get('bar');

Factory Class:

If your service is retrieved by calling a static method:

$sc = new ContainerBuilder();
$sc
->register('bar', '%bar.class%')
->setFactoryClass('%bar.class%')
->setFactoryMethod('getInstance')
->addArgument('Aarrg!!!')
;
$sc->setParameter('bar.class', 'Bar');
$sc->get('bar');

File Include:

For some services, especially those that are difficult or impossible to autoload, you may need the container to include a file before instantiating your class.

$sc = new ContainerBuilder();
$sc
->register('bar', '%bar.class')
->setFile('/path/to/file')
->addArgument('Aarrg!!!')
;
$sc->setParameter('bar.class', 'Bar');
$sc->get('bar');