Regex help

[niju]

Hi there
I need help to build a regex expression that matches
any alphanumeric word that has at least one number.

Any help would be much appreciated

Niju

 

[Verde]

Check out regexlib.com

 

[John Rivers]

some ideas to help you: (in t-sql format, sorry about that)

first check that it is alphanumeric
(ie: doesn't include anything out of that range)

like "%[^a-z0-9]%" (true = fail)

then check that at least one digit is present:

like "%[0-9]%" (true = succeed)

put it all together:

not var like "%[^a-z0-9]%" and var like "%[0-9]%"

only returns true for alphanumerics with at least one digit

now i will go and learn .net regex

 

[tom pester]

"any alphanumeric word that has at least one number" gives

(?=\w*\d)\w*

And to try it :

Try
Dim RegexObj As New Regex("(?=\w*\d)\w*")
Dim MatchResults As Match = RegexObj.Match(SubjectString)
While MatchResults.Success

MatchResults = MatchResults.NextMatch()
End While
Catch ex As ArgumentException
'Syntax error in the regular expression
End Try

It uses a technique called lookahead. It matches also single digital numbers.
If you dont want that :

(?=\w*\d)(?=\w*[a-z])\w*

Let me know if you have any more questions...

Cheers,
Tom Pester

 

[John Rivers]

thanks tom, you brought assertions in regular expressions alive for me

before i read your post i didn't have a clue what they were!

"any alphanumeric word that has at least one number" gives

(?=\w*\d)\w*

And to try it :

Try
Dim RegexObj As New Regex("(?=\w*\d)\w*")
Dim MatchResults As Match = RegexObj.Match(SubjectString)
While MatchResults.Success

MatchResults = MatchResults.NextMatch()
End While
Catch ex As ArgumentException
'Syntax error in the regular expression
End Try

It uses a technique called lookahead. It matches also single digital numbers.
If you dont want that :

(?=\w*\d)(?=\w*[a-z])\w*

Let me know if you have any more questions...

Cheers,
Tom Pester

Hi there
I need help to build a regex expression that matches
any alphanumeric word that has at least one number.
Any help would be much appreciated

Niju

 

[tom pester]

For more info on Zero-Width Assertions aka lookaround give this a try :

http://www.regular-expressions.info/lookaround.html

Cheers,
Tom Pester

thanks tom, you brought assertions in regular expressions alive for me

before i read your post i didn't have a clue what they were!

"any alphanumeric word that has at least one number" gives

(?=\w*\d)\w*

And to try it :

Try
Dim RegexObj As New Regex("(?=\w*\d)\w*")
Dim MatchResults As Match = RegexObj.Match(SubjectString)
While MatchResults.Success
MatchResults = MatchResults.NextMatch()
End While
Catch ex As ArgumentException
'Syntax error in the regular expression
End Try
It uses a technique called lookahead. It matches also single digital
numbers. If you dont want that :

(?=\w*\d)(?=\w*[a-z])\w*

Let me know if you have any more questions...

Cheers,
Tom Pester

Hi there
I need help to build a regex expression that matches
any alphanumeric word that has at least one number.
Any help would be much appreciated
Niju