Prado\Collections\TMap::contains PHP Метод

    public function contains($key)
    {
        return isset($this->_d[$key]) || array_key_exists($key, $this->_d);
    }

 /**
  * Returns whether the specified is in the map.
  * This overrides the parent implementation by converting the key to lower case first if CaseSensitive is false.
  * @param mixed the key
  * @return boolean whether the map contains an item with the specified key
  */
 public function contains($key)
 {
     return parent::contains($this->_caseSensitive ? $key : strtolower($key));
 }