How to Detect File in a Specifc Directory on Window Env?

Dear all I had a folder which contains a lot of pdf file, the name format of the pdf files are : xxxxx.dateformat.pdf (eg : abcdefg.20020718.pdf). Now i want to use the php script to detect what files it got in a specific folder. i want to make a user input form which will let user to input the date and then i will look for the pdf report from this specific folder base on the Date given! I think one of the quickest way is to ask php to check the filename from "Right to Left" which is the Date format! But i don't know which php function will perform this task (Check filename from Right to Left). If you have any other suggestion, pls help me! -- Thx a lot! Jack nedcor4@nedcor.com.hk