Wildcards and/or Regular Expressions

[yablonka]

Hi all,

 

I'm trying to create a very simple procedure in VB.NET that gets a string and gives back a boolean indicating if the string matches a certain template. For example...

 

if the string is: abcdefg

and the template is: *cd?f*

(* indicates zero or multiple characters and ? indicates a single character)

then in this case the string does match the template.

 

I'm trying to mess around with regular expression unsuccesfully.

 

Anyone?

(A sample code will be very helpful)

Thanks.

Edited October 16, 2003 by yablonka

[themster]

By using a parser you can build a regular expression from the template.

 

The template symbol * equals \w* in regex and ? equals \w.

 

Then try this:

 

Dim Template As String
Dim Pattern As String
Dim SearchString As String
Dim FoundMatch As Boolean
Dim i As Integer
Dim r As Regex

Template = "*cd?f*"
SearchString = "abcdefg"

For i = 0 To Len(Template) - 1
   Select Case Template.Substring(i, 1)
       Case "*"
           Pattern = Pattern + "\w*"
       Case "?"
           Pattern = Pattern + "\w"
       Case Else
           Pattern = Pattern + Template.Substring(i, 1)
   End Select
Next

FoundMatch = r.IsMatch(SearchString, Pattern)

 

In this case the regex pattern becomes \w*cd\wf\w* and the string matches the template.