使用 Symfony 5 中的 FOSRestBundle 转换单个属性以进行响应

Question

I'm working with numbers with a lot of decimal places in my symfony application. In my doctrine entity I have for example this property:

/**
 * @ORM\Column(type="float")
 */
private float $value;

In my mysql database I have this value for example: 0.00000000020828579949508

When I dump that in PHP I'm getting this: float(9.3722658865184E-7). I also made an API with the FOSRestBundle. In that API I want to return the value not in exponential form with at least 12 of it's decimal places. I think in that case I have to provide the value as string, correct? I figured out that I can convert it to string with something like this: sprintf("%.12f", $myEntity->getValue()) . But I have two questions now:

1. How can I convert a single property for response with the FOSRestBundle? So that I return the "value" property as string, even if it is a float normally.
2. Is there a general best practice or any tips to work with such numbers in symfony, doctrine and the FOSRestBundle?

Right now this is my controller action:

public function getData(): Response
{
    $repository = $this->getDoctrine()->getRepository(MyEntity::class);
    $data = $repository->findAll();

    return $this->handleView($this->view($data));
}

Answer 1

1. Assuming you are using Symfony version 3.x , you can use the JMS @Expose and @Accessor annotations to control how your entity property is serialized into response data. More info here . However, consider that JMS is bypassed if all you want is to pass your entity to the Twig template rendering engine.

2. The Doctrine float column type is the correct type to use when handling larger sized floating point numbers such as yours. Your issue is more related to the scientific notation that PHP is designed to use in order to represent these large floats. Allowing arithmetic such as 2.1E-10 + 2.2E-9 , but also requiring extra steps to convert their notation to a perhaps more human friendly readable form by using functions such as sprintf and number_format .