Symfony : how to construct the good relation between my entities? - php

Question

I'm a new user of Symfony, and I want to make a relation between 2 entities.
I have an entity named 'Suggest' and the other one 'Car'
Each suggest can have one or many cars, and a car can be used to 0 or multiple suggest
I want a new field named 'Cars' ( field for the name of cars) in my 'Suggest' entity, but I don't want new field in 'Car' entity
How can I do it ?
I tried to make a relation ManyToOne on my Suggest entity but it create me an id field of cars, and I can only put one.
with a ManyToMany relation, it is possible to get only a new field on my 'suggest' entity ?

Answer 1

Assuming you're using the make:entity command: if you add a cars property to your Suggest entity, and make it a ManyToMany relation to Car, it does not add an extra property to the Car class (you can say no to that):
Car:
<?php
namespace App\Entity;
use App\Repository\CarRepository;
use Doctrine\ORM\Mapping as ORM;
/**
* #ORM\Entity(repositoryClass=CarRepository::class)
*/
class Car
{
/**
* #ORM\Id
* #ORM\GeneratedValue
* #ORM\Column(type="integer")
*/
private $id;
public function getId(): ?int
{
return $this->id;
}
}
And Suggest:
<?php
namespace App\Entity;
use App\Repository\SuggestRepository;
use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;
/**
* #ORM\Entity(repositoryClass=SuggestRepository::class)
*/
class Suggest
{
/**
* #ORM\Id
* #ORM\GeneratedValue
* #ORM\Column(type="integer")
*/
private $id;
/**
* #ORM\ManyToMany(targetEntity=Car::class)
*/
private $cars;
public function __construct()
{
$this->cars = new ArrayCollection();
}
public function getId(): ?int
{
return $this->id;
}
/**
* #return Collection<int, Car>
*/
public function getCars(): Collection
{
return $this->cars;
}
public function addCar(Car $car): self
{
if (!$this->cars->contains($car)) {
$this->cars[] = $car;
}
return $this;
}
public function removeCar(Car $car): self
{
$this->cars->removeElement($car);
return $this;
}
}