Python code to use a regular expression to make sure a string is alphanumeric plus . - _

Posted by Warlax on Stack Overflow See other posts from Stack Overflow or by Warlax
Published on 2010-03-25T21:51:53Z Indexed on 2010/03/26 7:33 UTC
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python

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regex

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alphanumeric

Hi,

I looked and searched and couldn't find what I needed although I think it should be simple (if you have any Python experience, which I don't).

Given a string, I want to verify, in Python, that it contains ONLY alphanumeric characters: a-zA-Z0-9 and . _ -

examples:

Accepted:

bill-gates

Steve_Jobs

Micro.soft

Rejected:

Bill gates -- no spaces allowed

[email protected] -- @ is not alphanumeric

I'm trying to use:

if re.match("^[a-zA-Z0-9_.-]+$", username) == True:

But that doesn't seem to do the job...

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