is it possible get something from previous page??

Question

 

I have a complex quesion about pass argument from page to another page

 

I've a webpage which is  forum's list

when I run it on IE . which address is display like ? ?http://localhost/news/news_c.aspx?cid=26&FK=1?

and now I have to write a page (use C#) for forum's content

I would like to catch "cid" from address of previous page

is it possible? if yes. how can I do it? can somebody give me a tip to start it? ( which class should I use? which namespace should I import?? )

thanks ...

 

( if I don't make my question clearly ... please let me know I will explain it.. many thanks)