CListElementField::Delete

public function Delete()
{
	/** @global CStackCacheManager $stackCacheManager */
	global $stackCacheManager;
	if($this->_iblock_field["IS_REQUIRED"] == "Y")
	{
		if($this->_iblock_id > 0)
		{
			$arIBlockFields = CIBlock::GetArrayByID($this->_iblock_id, "FIELDS");
			$arIBlockFields[$this->_field_id]["IS_REQUIRED"] = "N";
			CIBlock::SetFields($this->_iblock_id, $arIBlockFields);
			$stackCacheManager->Clear("b_iblock");
		}
		$this->_iblock_field["IS_REQUIRED"] = "N";
	}

	parent::Delete();
	return true;
}