how to get last url parameters

how to get last url parameters

Hello,
I want to get lastest url paramater and add this paramater another url like that:
http://blabla.com/action.php?q=1&page=1&rows=50&sidx=id
to
http://blabla.com/action.php?q=5&page=1&rows=50&sidx=id

I tried out getUrlParam but it doesn't work with jqgrid thanks a lot.
King Regards,
Ibrahim
You can see the code below:

http://dpaste.com/76882/