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reference/constraints/UniqueEntity.rst

@@ -81,7 +81,7 @@
         // src/Entity/User.php
         namespace App\Entity;
 
         use Doctrine\ORM\Mapping as ORM;
         use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
         use Symfony\Component\Validator\Constraints as Assert;
 
@@ -100,6 +100,27 @@
             }
         }
 
+        // src/Form/Type/UserType.php
+        namespace App\Form\Type;
+
+        use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
+
+        class UserType extends AbstractType
+        {
+            // ...
+
+            public function configureOptions(OptionsResolver $resolver): void
+            {
+                $resolver->setDefaults([
+                    // ...
+                    'data_class' => User::class,
+                    'constraints' => [
+                        new UniqueEntity(fields: ['email']),
+                    ],
+                ]);
+            }
+        }
+
 .. warning::
 
     This constraint doesn't provide any protection against `race conditions`_.
@@ -116,13 +137,14 @@
 Using a PHP class
 -----------------
 
-This constraint can also check **uniqueness on any PHP class** and not only on
-Doctrine entities. Consider the following Doctrine entity::
+This constraint can also check **uniqueness on any PHP class** that is mapped to
+a Doctrine entity, and not only on Doctrine entities. Consider the following
+Doctrine entity::
 
     // src/Entity/User.php
     namespace App\Entity;
 
     use Doctrine\ORM\Mapping as ORM;
 
     #[ORM\Entity]
     class User
@@ -160,8 +182,6 @@
         )]
         class UserDto
         {
-            public ?int $id = null,
-
             #[Assert\Email]
             public ?string $email = null;
         }
@@ -208,8 +228,6 @@
 
         class UserDto
         {
-            public ?int $id = null;
-
             public ?string $email = null;
 
             public static function loadValidatorMetadata(ClassMetadata $metadata): void
@@ -353,7 +371,7 @@
 as long as they don't have the same name also).
 
 If you need to require two fields to be individually unique (e.g. a unique
-``email`` and a unique ``username``), you should use two ``UniqueEntity`` entries,
+``email`` and a unique ``username``), you must use two ``UniqueEntity`` entries,
 each with a single field.
 
 When `using a PHP class`_, the names of the unique fields may differ
@@ -721,6 +739,10 @@
             }
         }
 
+.. note::
+
+    This option has no effect when the constraint is applied to an entity.
+
 ``message``
 ~~~~~~~~~~~