respect-validation/docs/validators/KeyExists.md

KeyExists

• KeyExists(string|int $key)

Validates if the given key exists in an array.

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

v::keyExists('name')->assert(['email' => 'therespectpanda@gmail.com']);
// → `.name` must be present

v::keyExists(0)->assert(['a', 'b', 'c']);
// Validation passes successfully

v::keyExists(4)->assert(['a', 'b', 'c']);
// → `.4` must be present

v::keyExists('username')->assert(new ArrayObject(['username' => 'therespectpanda']));
// Validation passes successfully

v::keyExists(5)->assert(new ArrayObject(['a', 'b', 'c']));
// → `.5` must be present

Notes

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

Templates

KeyExists::TEMPLATE_STANDARD

Mode	Template
default	{{subject}} must be present
inverted	{{subject}} must not be present

Template placeholders

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

Caveats

KeyExists defines the given $key as the path, and because it is a standalone validator without children, it's not possible to display a fully custom name with it.

When no custom name is set, the path is displayed as {{name}}. When a custom name is set, the validation engine prepends the path to the custom name:

v::keyExists('foo')->assert([]);
// → `.foo` must be present

v::named('Custom name', v::keyExists('foo'))->assert([]);
// → `.foo` (<- Custom name) must be present

If you want to display only a custom name while checking if a key exists, use Key with AlwaysValid:

v::key('foo', v::named('Custom name', v::alwaysValid()))->assert([]);
// → Custom name must be present

Categorization

• Arrays
• Structures

Changelog

Version	Description
3.0.0	Created from Key

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See also:

• AlwaysValid
• ArrayType
• ArrayVal
• Each
• Key
• KeyOptional
• Property
• PropertyExists
• PropertyOptional