extract date from string using script task

Hi-

I have some flat files with name as:

"abc20120212"
"YYYYYYY20110909".....and so on

I'm creating SSIS package to transfer data from multiple flat files to a destination table. I  have to extract the date from file name and according to that date destination will be set

So how I can read files and extract date from the file name and use that date in making condition ,using script task. I need to use script task in control flow level so that i can set my destination.C# code can be more helpful.

Pls help. Its urgent

j