Unique ====== Validates that all the elements of the given collection are unique (none of them is present more than once). Elements are compared strictly, so ``'7'`` and ``7`` are considered different elements (a string and an integer, respectively). .. seealso:: If you want to apply different validation constraints to the elements of a collection or want to make sure that certain collection keys are present, use the :doc:`Collection constraint `. .. seealso:: If you want to validate that the value of an entity property is unique among all entities of the same type (e.g. the registration email of all users) use the :doc:`UniqueEntity constraint `. ========== =================================================================== Applies to :ref:`property or method ` Options - `groups`_ - `message`_ - `payload`_ Class :class:`Symfony\\Component\\Validator\\Constraints\\Unique` Validator :class:`Symfony\\Component\\Validator\\Constraints\\UniqueValidator` ========== =================================================================== Basic Usage ----------- This constraint can be applied to any property of type ``array`` or ``\Traversable``. In the following example, ``$contactEmails`` is an array of strings: .. configuration-block:: .. code-block:: php-annotations // src/Entity/Person.php namespace App\Entity; use Symfony\Component\Validator\Constraints as Assert; class Person { /** * @Assert\Unique */ protected $contactEmails; } .. code-block:: yaml # config/validator/validation.yaml App\Entity\Person: properties: contactEmails: - Unique: ~ .. code-block:: xml .. code-block:: php // src/Entity/Person.php namespace App\Entity; use Symfony\Component\Validator\Constraints as Assert; use Symfony\Component\Validator\Mapping\ClassMetadata; class Person { public static function loadValidatorMetadata(ClassMetadata $metadata) { $metadata->addPropertyConstraint('contactEmails', new Assert\Unique()); } } Options ------- .. include:: /reference/constraints/_groups-option.rst.inc message ~~~~~~~ **type**: ``string`` **default**: ``This collection should contain only unique elements.`` This is the message that will be shown if at least one element is repeated in the collection. You can use the following parameters in this message: ============================= ================================================ Parameter Description ============================= ================================================ ``{{ value }}`` The repeated value ============================= ================================================ .. include:: /reference/constraints/_payload-option.rst.inc