Skip to content
  • About
    • What is Symfony?
    • Community
    • News
    • Contributing
    • Support
  • Documentation
    • Symfony Docs
    • Symfony Book
    • Screencasts
    • Symfony Bundles
    • Symfony Cloud
    • Training
  • Services
    • SensioLabs Professional services to help you with Symfony
    • Platform.sh for Symfony Best platform to deploy Symfony apps
    • SymfonyInsight Automatic quality checks for your apps
    • Symfony Certification Prove your knowledge and boost your career
    • Blackfire Profile and monitor performance of your apps
  • Other
  • Blog
  • Download
sponsored by SensioLabs
  1. Home
  2. Documentation
  3. Reference
  4. Constraints
  5. Blank
  • Documentation
  • Book
  • Reference
  • Bundles
  • Cloud

Table of Contents

  • Basic Usage
  • Options
    • message
    • payload

Blank

Edit this page

Warning: You are browsing the documentation for Symfony 4.1, which is no longer maintained.

Read the updated version of this page for Symfony 6.2 (the current stable version).

Blank

Validates that a value is blank - meaning equal to an empty string or null:

1
2
3
if ('' !== $value && null !== $value) {
    // validation will fail
}

To force that a value strictly be equal to null, see the IsNull constraint.

To force that a value is not blank, see NotBlank. But be careful as NotBlank is not strictly the opposite of Blank.

Applies to property or method
Options
  • message
  • payload
Class Blank
Validator BlankValidator

Basic Usage

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

1
2
3
4
5
6
7
8
9
10
11
12
// src/Entity/Author.php
namespace App\Entity;

use Symfony\Component\Validator\Constraints as Assert;

class Author
{
    /**
     * @Assert\Blank
     */
    protected $firstName;
}
1
2
3
4
5
# config/validator/validation.yaml
App\Entity\Author:
    properties:
        firstName:
            - Blank: ~
1
2
3
4
5
6
7
8
9
10
11
12
<!-- config/validator/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="App\Entity\Author">
        <property name="firstName">
            <constraint name="Blank" />
        </property>
    </class>
</constraint-mapping>
1
2
3
4
5
6
7
8
9
10
11
12
13
// src/Entity/Author.php
namespace App\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', new Assert\Blank());
    }
}

Options

message

type: string default: This value should be blank.

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

You can use the following parameters in this message:

Parameter Description
{{ value }} The current (invalid) value

payload

type: mixed default: null

This option can be used to attach arbitrary domain-specific data to a constraint. The configured payload is not used by the Validator component, but its processing is completely up to you.

For example, you may want to use several error levels to present failed constraints differently in the front-end depending on the severity of the error.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.
TOC
    Version
    We stand with Ukraine.
    Version:
    Measure & Improve Symfony Code Performance

    Measure & Improve Symfony Code Performance

    Check Code Performance in Dev, Test, Staging & Production

    Check Code Performance in Dev, Test, Staging & Production

    Symfony footer

    ↓ Our footer now uses the colors of the Ukrainian flag because Symfony stands with the people of Ukraine.

    Avatar of VisionPages, a Symfony contributor

    Thanks VisionPages for being a Symfony contributor

    1 commit • 2 lines changed

    View all contributors that help us make Symfony

    Become a Symfony contributor

    Be an active part of the community and contribute ideas, code and bug fixes. Both experts and newcomers are welcome.

    Learn how to contribute

    Symfony™ is a trademark of Symfony SAS. All rights reserved.

    • What is Symfony?

      • Symfony at a Glance
      • Symfony Components
      • Case Studies
      • Symfony Releases
      • Security Policy
      • Logo & Screenshots
      • Trademark & Licenses
      • symfony1 Legacy
    • Learn Symfony

      • Symfony Docs
      • Symfony Book
      • Reference
      • Bundles
      • Best Practices
      • Training
      • eLearning Platform
      • Certification
    • Screencasts

      • Learn Symfony
      • Learn PHP
      • Learn JavaScript
      • Learn Drupal
      • Learn RESTful APIs
    • Community

      • SymfonyConnect
      • Support
      • How to be Involved
      • Code of Conduct
      • Events & Meetups
      • Projects using Symfony
      • Downloads Stats
      • Contributors
      • Backers
    • Blog

      • Events & Meetups
      • A week of symfony
      • Case studies
      • Cloud
      • Community
      • Conferences
      • Diversity
      • Documentation
      • Living on the edge
      • Releases
      • Security Advisories
      • SymfonyInsight
      • Twig
      • SensioLabs
    • Services

      • SensioLabs services
      • Train developers
      • Manage your project quality
      • Improve your project performance
      • Host Symfony projects

      Deployed on

    Follow Symfony