respect-validation/docs/validators/KeyOptional.md

KeyOptional

• KeyOptional(string|int $key, Validator $validator)

Validates the value of an array against a given validator when the key exists.

v::keyOptional('name', v::stringType())->assert([]);
// Validation passes successfully

v::keyOptional('name', v::stringType())->assert(['name' => 'The Respect Panda']);
// Validation passes successfully

v::keyOptional('email', v::email())->assert([]);
// Validation passes successfully

v::keyOptional('email', v::email())->assert(['email' => 'therespectpanda@gmail.com']);
// Validation passes successfully

v::keyOptional('age', v::intVal())->assert(['age' => 'Twenty-Five']);
// → `.age` must be an integer value

The name of this validator is automatically set to the key name.

v::keyOptional('age', v::intVal())->assert(['age' => 'Twenty-Five']);
// → `.age` must be an integer value

Note

This validator will pass for anything that is not an array because it will always pass when it doesn't find a key. If you want to ensure the input is an array, use ArrayType with it.

v::arrayType()->keyOptional('phone', v::phone())->assert('This is not an array');
// → "This is not an array" must be an array

Below are some other validators that are tightly related to KeyOptional:

• To validate if a key exists, use KeyExists instead.
• To validate an array against a given validator requiring the key to exist, use Key instead.

Templates

Template placeholders

Placeholder	Description
subject	The validated input or the custom validator name (if specified).

Categorization

• Arrays
• Structures

Changelog

Version	Description
3.0.0	Created from Key

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See also:

• ArrayType
• ArrayVal
• Each
• Key
• KeyExists
• Property
• PropertyExists
• PropertyOptional