$validator->validate($data); if ($validator->fails()) { $errors = $validator->getErrors(); foreach ($errors as $error) { echo $error . '
'; } }
$errors = $validator->setRules($rules)->validate($data)->getErrors();In this example, the `setRules()` method is used to set the validation rules for the data. The `validate()` method is then called with the data parameter to validate the data. If the validation fails, the `$errors` variable is assigned to the error messages returned by the `getErrors()` method. Possible libraries that can be used for this feature are Laravel's Validator, Symfony's Validator, and CakePHP's Validator.