Re: Help with Regex and trying to mimic the VB "like" comparison

From: Niki Estner (niki.estner_at_cube.net)
Date: 06/15/04 

Date: Tue, 15 Jun 2004 18:48:05 +0200

After a brief look, I think this code won't work for strings containing
backslashes, braces, or any other Regex-metacharacters.
I'd suggest using Regex.Escape(...) to escape all the meta-characters in the
pattern, and then replacing "\*" to ".*", and "\?" to ".", and adding the
"^"/"$" prefix/suffix.

Niki

PS: Maybe your users would be glad if they had the choice to use the whole
power of Regex's, too (optionally, of course). Like in the Search-Replace
dialog of VS.

"Andrew Baker" <webmaster@vbusers.com> wrote in
news:c19b84e5.0406150720.1fb221c3@posting.google.com...
> FYI have managed to bodge something together below which seems to work:
>
>
http://www.vbusers.com/codecsharp/codeget.asp?ThreadID=25&PostID=1&NumReplies=0
>
> andrew
>
> "Beeeeeeeeeeeeves" <Beeeeeeeeeeeeves@discussions.microsoft.com> wrote in
message news:<DB0F13A1-8FC8-4210-A888-E312CA820A56@microsoft.com>...
> > You can use regexes, just allow the pattern the user types be the
pattern for the regex, but with a few precautions:
> > 1) Any characters they type that are regex escapes, you'll need to
prefix them with \ to let the regex know they are literals, but beware that
you may not want to allow these in the filename anyway.
> > See
> >
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpgenref/html/cpconRegularExpressionsLanguageElements.asp
(watch for wordwrap)
> > 2)
> >
> > "Andrew Baker" wrote:
> >
> > > I am trying to write a function which provides my users with a file
> > > filter. The filter used to work just using the VB "Like" comparision,
> > > but I can't find the equivilant in C#. I looked at RegEx.IsMatch but
> > > it behaves quite differently. Is there a way I can mimic the DOS
> > > filtering of filenames (eg. "*.*" or "*" returns all files, "*.xls"
> > > returns all excel files, "workbook*" returns all files begining with
> > > "workbook" etc)?
> > >
> > > thanks in advance...
> > >
> > > andrew
> > >

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