if by "filetype" you mean a 3 byte extension (like .pas or .txt) and you can constrain the character set (say to case-indifferent alpha, digits and a few special characters like '$' and ' ' and '_') then you have about 40^3 (about 65k) possible file types.
you could comfortably hold an array of 65k byte codes for "include/exclude/whatever" and map each 3byte filetype directly to an integer index into this array. BTW you can use a similar trick to quickly generate the index into the table from the 3 byte filetype: construct 3 tables of 256 integers (1 for each possible character in each of the 3 positions 1,2,3 of the filetype) - then sum those integers to create the index into the 65k array. if you have a lot of filetypes this will be faster than doing searching lookups into a table of 65000 codes. -ns http://www.roserox.co.th ----- Original Message ----- From: "Alistair George" <[EMAIL PROTECTED]> To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> Sent: Tuesday, October 15, 2002 07:02 Subject: [DUG]: To CASE or not? > Hi all. > I am writing a backup routine which includes or excludes bunches of > files/folders. > For example, during the backup process the compressor must be told which file > types to exclude. > My concern is that if this bunch of types is numerous that the > processing/parsing could be quite resource intensive. > > Any suggestions to achieve this would be appreciated. My own feeling is to run > with a dynamic CASE statement, but even this would seem to take a pretty big > chunk of processing time given each file is parsed? > Thanks, > Alistair George+ > > -------------------------------------------------------------------------- - > New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] > Website: http://www.delphi.org.nz > To UnSub, send email to: [EMAIL PROTECTED] > with body of "unsubscribe delphi" > Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/ --------------------------------------------------------------------------- New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] Website: http://www.delphi.org.nz To UnSub, send email to: [EMAIL PROTECTED] with body of "unsubscribe delphi" Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
