This is an TYPO3 / Extbase Example on how to Validate some Properties in the Controller - this is usefull for conditonal Validation

extabase_in_controller_action_validation_example.php

<?php

class foo {

	/**
	 * keep trac if we have created a custom error.
	 * @var boolean
	 */
	protected $hasCustomError = false;

	/**
	 * Dies beispiel zeigt wie die validierung manuell durchführt.
	 * @param  namespace\package\Domain\Model\MyModelWithoutValidation $myObjectWithoutValidation dieses model besitzt keine Validierung annotations
	 * wir geben auch keine manuell @validate an so das die controller action argument nicht validiert wird.
	 */
	public function myCustomAction($myObjectWithoutValidation){
		//** da wir werde validierung im moden noch im kontroller haben müssen wir nun die validierung manuell durchführen.
		//** hier validieren wir eine email adresse auf "füllung" und email und das sie nicht länger als 50 zeichen ist (weil z.b unser DB feld nicht länger ist).

		$emailValue = $MyModelWithoutValidation-getEmail();
		$this->validatePropertyByValidator('email',$emailValue,'NotEmpty');
		$this->validatePropertyByValidator('email',$emailValue,'EmailAddress');
		$this->validatePropertyByValidator('email',$emailValue,'StringLength',array('maximum'=>50));

		// if a custom validation Error has been triggered
		if($this->hasCustomError){
			$this->errorAction();
		}

	}

	/**
	 * Validates property by a given validator and genereated the correct errors for handling
	 * usful for validating conditional properties in conroller
	 * @param  string $propertyName  the name of the property to be validated
	 * @param  mixed  $propertyValue the value to be validated
	 * @param  string $validatorName full class name of the validator or short form for Default Extbase Validators
	 * @param  mixed $validatorParameters the parameter array for the given Validator or NULL
	 * @return boolean               returns the validation result
	 */
	protected function validatePropertyByValidator($propertyName, $propertyValue, $validatorName, $validatorParameters=NULL){
		$validatorName = $this->getValidatorClassNameFromShortName($validatorName);
		if(TYPO3_branch == '4.5'){
			$validator = $this->objectManager->get($validatorName);
			if(is_array($validatorParameters)){
				$validator->setOptions($validatorParameters);
			}
		}else{
			if(is_null($validatorParameters)){
				$validatorParameters = array();
			}
			$validator = $this->objectManager->get($validatorName, $validatorParameters);
		}
		$result = $validator->isValid($propertyValue);
		$errors = $validator->getErrors();
		foreach($errors as $currentError){
			$this->addCustomError($propertyName,$currentError->getMessage(), $currentError->getCode());
		}
		return $result;
	}

	/**
	 * Returns the Full Class name form a Short "validator name"
	 * @param  string $validatorName the name of the validator
	 * @return string                the full classname
	 */
	protected function getValidatorClassNameFromShortName($validatorName){
		if(substr($validatorName, 0,3) === 'Tx_'){
			return $validatorName;
		}
		if(TYPO3_branch == '4.5'){
			$validatorName = 'Tx_Extbase_Validation_Validator_'.$validatorName.'Validator';
		}elseif( substr($validatorName,0,1) != '\\'){
			$validatorName = '\\TYPO3\CMS\\Extbase\\Validation\\Validator\\'.$validatorName.'Validator';
		}
		return $validatorName;
	}

	/**
	 * Creates a Custom Error for Attributes wich are Evaluated in the Controller
	 * @param string $propertyName name of the property with an error
	 * @param string $message      the default message if not Translated
	 * @param integer $code        the error code needs to be unique
	 */
	protected function addCustomError($propertyName,$message,$code){
		$error = $this->objectManager->get('Tx_Extbase_MVC_Controller_ArgumentError', $propertyName);
		$propertyErrors = array();
		$propertyErrors[$propertyName] = $this->objectManager->get('Tx_Extbase_Validation_Error',$message,$code);
		$error->addErrors($propertyErrors);
		$this->propertyMapper->getMappingResults()->addError($error,$propertyName);
		$this->hasCustomError = true;
	}
}

?>