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Symfony2 – Franz Jordán 2011
php app/console doctrine:generate:entity --entity="AcmeStoreBundle:Category" --
fields="name:string(255)"
This task generates the Category entity for you, with an id field, a name field and the
associated getter and setter functions.
Relationship Mapping Metadata
To relate the Category and Product entities, start by creating a products property on
the Categoryclass:
// src/Acme/StoreBundle/Entity/Category.php
// ...
use Doctrine\Common\Collections\ArrayCollection;
class Category
{
// ...
/**
* @ORM\OneToMany(targetEntity="Product", mappedBy="category")
*/
protected $products;
}
public function __construct()
{
}
$this->products = new ArrayCollection();
First, since a Category object will relate to many Product objects, a products array property is
added to hold those Product objects. Again, this isn't done because Doctrine needs it, but
instead because it makes sense in the application for each Category to hold an array
of Product objects.
The code in the __construct() method is important because Doctrine requires
the$products property to be an ArrayCollection object. This object looks and acts
almost exactly like an array, but has some added flexibility. If this makes you uncomfortable,
don't worry. Just imagine that it's an array and you'll be in good shape.
Next, since each Product class can relate to exactly one Category object, you'll want to add
a$category property to the Product class:
// src/Acme/StoreBundle/Entity/Product.php
// ...
class Product
{
// ...
}
/**
* @ORM\ManyToOne(targetEntity="Category", inversedBy="products")
* @ORM\JoinColumn(name="category_id", referencedColumnName="id")
*/
protected $category;
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