1# KeyNested 2 3- `v::keyNested(string $name)` 4- `v::keyNested(string $name, v $validator)` 5- `v::keyNested(string $name, v $validator, boolean $mandatory = true)` 6 7Validates an array key or an object property using `.` to represent nested data. 8 9Validating keys from arrays or `ArrayAccess` instances: 10 11```php 12$array = [ 13 'foo' => [ 14 'bar' => 123, 15 ], 16]; 17 18v::keyNested('foo.bar')->validate($array); // true 19``` 20 21Validating object properties: 22 23```php 24$object = new stdClass(); 25$object->foo = new stdClass(); 26$object->foo->bar = 42; 27 28v::keyNested('foo.bar')->validate($object); // true 29``` 30 31This rule was inspired by [Yii2 ArrayHelper][]. 32 33*** 34See also: 35 36 * [Attribute](Attribute.md) 37 * [Key](Key.md) 38 39 40[Yii2 ArrayHelper]: https://github.com/yiisoft/yii2/blob/68c30c1/framework/helpers/BaseArrayHelper.php "Yii2 ArrayHelper" 41