Hi
I have a process that requires a user to open one of several different xls
files, each has a specific format and I wish to decide which type of file
the user has opened.
Row one comprises a set of column headings which for each file type should
be the same, I plan to store a signature based on these headings and check
the file just opened against each of these signatures. My question is what
is best way of creating these signatures ?

I had considered using a concatenation of each column heading (trimmed) but
in some cases the signature is over 1000 characters. Is there some form of
encoding I can use to convert these into a shorter string that will detect
the file type and most cases spot if the user opens a un-recognised file
type or the source file headings have changed in some way?

TIA

--
Cheers
Nigel