<?php
/**
 * TActiveControlAdapter and TCallbackPageStateTracker class file.
 *
 * @author Wei Zhuo <weizhuo[at]gamil[dot]com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2014 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @package Prado\Web\UI\ActiveControls
 */

namespace Prado\Web\UI\ActiveControls;

/**
 * TScalarDiff class.
 *
 * Calculate the changes to a scalar value.
 *
 * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
 * @package Prado\Web\UI\ActiveControls
 * @since 3.1
 */
class TScalarDiff extends TViewStateDiff
{
	/**
	 * @return mixed update viewstate value.
	 */
	public function getDifference()
	{
		if(gettype($this->_new) === gettype($this->_old)
			&& $this->_new === $this->_old)
			return $this->_null;
		else
			return $this->_new;
	}
}