PHP DateTime Object Extension

DateTime.php

/**
 * EC_DateTime
 *
 * By default in the PHP object, the date property is not affected when the 
 * method format() is run. However, it's annoying to have to constantly set
 * the format you desire to output. Also, you may not have access when the
 * __toString() method is executed in another function if passed as an object.
 * and then treated as a string.
 *
 * So what this object allows for us to do is to access that formatted date
 * and also to echo the $date variable that holds our EC_DateTime Object 
 * 
 * @author	Joel Kallman
 */ 
class EC_DateTime extends DateTime {
	
	/**
	 * Current Format
	 * 
	 * Defaults to "Y-m-d H:i:s". 
	 * You can set directly: $date->format = 'Y-m-d H:i:s';
	 * 
	 * @access	public
	 * @var		string
	 */
	public $format = 'Y-m-d H:i:s';
	
	// ----------------------------------------------------------------------------------------
	
	/**
	 * Format
	 * 
	 * The change this function introduces is the ability to 
	 * get the latest state of the formatted date from the object
	 * 
	 * @param	string	Optional. If not provided it will use the last format OR default
	 * @return	string
	 */
	public function format($format = '')
	{
		$this->format = ( ! empty($format)) ? $format: $this->format;
		return parent::format($this->format);		
	}
	
	// ----------------------------------------------------------------------------------------
	
	/**
	 * Copy
	 * 
	 * @return	object DateTime Object
	 */
	public function copy()
	{
		return new EC_DateTime($this->format('Y-m-d H:i:s'), $this->getTimezone());
	}
	
	// ----------------------------------------------------------------------------------------
	
	/**
	 * __toString
	 *
	 * Outputs Most Recently Formatted Date
	 */
	public function __toString() 
	{
		return $this->format();
    }
}