For ur first question  u can do one thing, u can store all the required file
names in one array variable and then can rotate the loop and perform required
operations. Also another option is that you can directly retrieve all the
required files  from the required folder  as following.

For each files in System.io.directory.getfiles("C:\Data")
'''in this loop perform all required operations for given
file.''''''''''
Although above code  in VB.NET for VB u can do the same thing. But for VB i don't
remember particular function for retrieving files, I think u must be knowing.


And for ur second question, I am not getting what u want. Then also i m sending
u reply wht i m getting from ur question.
For ur second question's solution, u can rotate a loop and can perform the same
operation. Initally just u need to fix one criteria.