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Null

2.1 version
Unmaintained

Null

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.

Applies to property or method
Options
Class Symfony\Component\Validator\Constraints\Null
Validator Symfony\Component\Validator\Constraints\NullValidator

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:

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    # src/Acme/BlogBundle/Resources/config/validation.yml
    Acme\BlogBundle\Entity\Author:
        properties:
            firstName:
                - 'Null': ~
    
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    // src/Acme/BlogBundle/Entity/Author.php
    namespace Acme\BlogBundle\Entity;
    
    use Symfony\Component\Validator\Constraints as Assert;
    
    class Author
    {
        /**
         * @Assert\Null()
         */
        protected $firstName;
    }
    
  • XML
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    <!-- src/Acme/BlogBundle/Resources/config/validation.xml -->
    <class name="Acme\BlogBundle\Entity\Author">
        <property name="firstName">
            <constraint name="Null" />
        </property>
    </class>
    
  • PHP
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    // src/Acme/BlogBundle/Entity/Author.php
    namespace Acme\BlogBundle\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\Null());
        }
    }
    

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.