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Luhn

Luhn

New in version 2.2: The Luhn constraint was introduced in Symfony 2.2.

This constraint is used to ensure that a credit card number passes the Luhn algorithm. It is useful as a first step to validating a credit card: before communicating with a payment gateway.

Applies to property or method
Options
Class Symfony\Component\Validator\Constraints\Luhn
Validator Symfony\Component\Validator\Constraints\LuhnValidator

Basic Usage

To use the Luhn validator, simply apply it to a property on an object that will contain a credit card number.

  • Annotations
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    // src/AppBundle/Entity/Transaction.php
    namespace AppBundle\Entity;
    
    use Symfony\Component\Validator\Constraints as Assert;
    
    class Transaction
    {
        /**
         * @Assert\Luhn(message = "Please check your credit card number.")
         */
        protected $cardNumber;
    }
    
  • YAML
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    # src/AppBundle/Resources/config/validation.yml
    AppBundle\Entity\Transaction:
        properties:
            cardNumber:
                - Luhn:
                    message: Please check your credit card number.
    
  • XML
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    <!-- 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\Transaction">
            <property name="cardNumber">
                <constraint name="Luhn">
                    <option name="message">Please check your credit card number.</option>
                </constraint>
            </property>
        </class>
    </constraint-mapping>
    
  • PHP
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    // src/AppBundle/Entity/Transaction.php
    namespace AppBundle\Entity;
    
    use Symfony\Component\Validator\Mapping\ClassMetadata;
    use Symfony\Component\Validator\Constraints as Assert;
    
    class Transaction
    {
        protected $cardNumber;
    
        public static function loadValidatorMetadata(ClassMetadata $metadata)
        {
            $metadata->addPropertyConstraint('cardNumber', new Assert\Luhn(array(
                'message' => 'Please check your credit card number',
            )));
        }
    }
    

Available Options

message

type: string default: Invalid card number.

The default message supplied when the value does not pass the Luhn check.

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