php - Zend Framework 2 教程“学习依赖注入”缺少示例

Question

（在一些非常（！）有用的关于 DI 的文章和一个基本示例的链接之后）在“最简单的用例（2 个类，一个消耗另一个） ”一章中，Zend Framework 2 教程“学习依赖注入”提供了构造函数的示例注射。这个还行。然后它显示了一个setter 注入的例子。但它并不完整（缺少示例的调用/使用部分）。缺少接口注入和基于注释的注入的示例。

(1) setter 注入示例的缺失部分如何？有人可以用教程中的类写一个（2）接口注入和（3）基于注释的注入示例吗？

先感谢您！

Answer 1

You probably want to look into Ralph Schindler's Zend\Di examples, which cover all the various Zend\Di use cases.

I also started working on the Zend\Di documentation, but never got to finish it because I was too busy with other stuff (will eventually pick it up again).

Setter injection (enforced):

class Foo 
{
    public $bar;

    public function setBar(Bar $bar)
    {
        $this->bar = $bar;
    }
}

class Bar 
{
}

$di  = new Zend\Di\Di;
$cfg = new Zend\Di\Configuration(array(
    'definition' => array(
        'class' => array(
            'Foo' => array(
                // forcing setBar to be called
                'setBar' => array('required' => true)
            )
        )
    )
)));

$foo = $di->get('Foo');

var_dump($foo->bar); // contains an instance of Bar

Setter injection (from given parameters):

class Foo 
{
    public $bar;

    public function setBar($bar)
    {
        $this->bar = $bar;
    }
}

$di     = new Zend\Di\Di;
$config = new Zend\Di\Configuration(array(
    'instance' => array(                
        'Foo' => array(
            // letting Zend\Di find out there's a $bar to inject where possible
            'parameters' => array('bar' => 'baz'),
        )
    )
)));
$config->configure($di);

$foo = $di->get('Foo');

var_dump($foo->bar); // 'baz'

Interface injection. Zend\Di discovers injection methods from an *Aware* interface as defined in the introspection strategy:

interface BarAwareInterface
{
    public function setBar(Bar $bar);
}

class Foo implements BarAwareInterface
{
    public $bar;

    public function setBar(Bar $bar)
    {
        $this->bar = $bar;
    }
}

class Bar 
{
}


$di  = new Zend\Di\Di;
$foo = $di->get('Foo');

var_dump($foo->bar); // contains an instance of Bar

Annotation injection. Zend\Di discovers injection methods via annotations:

class Foo 
{
    public $bar;

    /**
     * @Di\Inject()
     */
    public function setBar(Bar $bar)
    {
        $this->bar = $bar;
    }
}

class Bar 
{
}


$di  = new Zend\Di\Di;
$di
    ->definitions()
    ->getIntrospectionStrategy()
    ->setUseAnnotations(true);

$foo = $di->get('Foo');

var_dump($foo->bar); // contains an instance of Bar