Well, a split using '_' will get you "Date1", "Date2" and "type.asp", the last you can probably drop. From there, it's a rather easy (!) application of sort: 
# this searches on Date1
my @sorted_list = sort {
   ${split(/_/,$a)}[0] cmp ${split(/_/,$b)}[0] } @list;
       # [0] is Date1, [1] is Date2, [2] is type.asp

[download]
You could also apply the so called Schwartian Transform if your Dates are not directly compariable and need a special function: 
my @sorted_list = 
   map { $_[0] }
   sort { date_compare($a[1],$b[1]) }  
      # [1] is Date1, [2] is Date2, [3] is the type.asp
   map { [ $_, split /_/ ] } @list;

[download]
Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

In reply to Re: How do I sort by certain parts of a filename? by Masem
in thread How do I sort by certain parts of a filename? by wstarrs

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