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IsNull

2.3 version

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Unmaintained

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IsNull
- Basic Usage
- Options
  - message

IsNull¶

Validates that a value is exactly equal to null. To force that a property is simply blank (blank string or null), see the Blank constraint. To ensure that a property is not null, see NotNull.

Also see NotNull.

Applies to	property or method
Options	message
Class	`IsNull`
Validator	`IsNullValidator`

Basic Usage¶

If, for some reason, you wanted to ensure that the firstName property of an Author class exactly equal to null, you could do the following:

Annotations

// src/AppBundle/Entity/Author.php
namespace AppBundle\Entity;

use Symfony\Component\Validator\Constraints as Assert;

class Author
{
    /**
     * @Assert\IsNull()
     */
    protected $firstName;
}

YAML

# src/AppBundle/Resources/config/validation.yml
AppBundle\Entity\Author:
    properties:
        firstName:
            - 'IsNull': ~

XML

<!-- src/AppBundle/Resources/config/validation.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<constraint-mapping xmlns="http://symfony.com/schema/dic/constraint-mapping"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://symfony.com/schema/dic/constraint-mapping http://symfony.com/schema/dic/constraint-mapping/constraint-mapping-1.0.xsd">

    <class name="AppBundle\Entity\Author">
        <property name="firstName">
            <constraint name="IsNull" />
        </property>
    </class>
</constraint-mapping>

PHP

// src/AppBundle/Entity/Author.php
namespace AppBundle\Entity;

use Symfony\Component\Validator\Mapping\ClassMetadata;
use Symfony\Component\Validator\Constraints as Assert;

class Author
{
    public static function loadValidatorMetadata(ClassMetadata $metadata)
    {
        $metadata->addPropertyConstraint('firstName', Assert\IsNull());
    }
}

Options¶

message¶

type: string default: This value should be null.

This is the message that will be shown if the value is not null.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.