//Get the page path e.g. /category/sub-category/sompage.html
JUri::getInstance()->toString(array('path'));

//Get the page path with query string e.g. /category/sub-category/sompage.html?param=val&param2=val2
JUri::getInstance()->toString(array('path','query'));

//Retreive just the query string
JUri::getInstance()->getQuery()

or

JUri::getInstance()->toString(array('query'));

Can use JUri to get the page handle

Getting Page Path and Query String With JUri

joomla

PHP