regular expression

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Christine Mayer - 15 Oct 2007 11:34 GMT

Hi,

I need a regular expression - it should:

Allow all Strings that do not begin with "car_"

Examples - ok would be:
car
carwash
1
a
1234
abcdefgh
a1b2

not ok was:
car_
car_1
car_a
car_1234
car_abcdefgh
car_a1b2

On Google, I basically found the expression:
.*(?<!car_)wash

On its basis, I build:
(?<!car_)[0-9A-Za-z_+\-]+

However, it doesn't work as required - I guess, because the String
that follows
defined by "0-9A-Za-z_+\-" could be "car_" too! In other words, this
rule says
Don't start the String with "car_" but after that you may write car_ -
so the String MAY begin with car_

Any idea how to fix that?

Thx,

Christine

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Gordon Beaton - 15 Oct 2007 12:17 GMT

> I need a regular expression - it should:
>
> Allow all Strings that do not begin with "car_"

e.g.

"^(?!car_)[a-zA-Z0-9_+-]*"

/gordon

--

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Christian - 15 Oct 2007 12:21 GMT

Gordon Beaton schrieb:

>> I need a regular expression - it should:
>>
[quoted text clipped - 7 lines]
>
> --

though that won't match if the string contains a linefeed..

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Gordon Beaton - 15 Oct 2007 12:28 GMT

> though that won't match if the string contains a linefeed..

It won't make coffee either, but the original poster didn't ask for
either of those things.

/gordon

--

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Piotr Kobzda - 15 Oct 2007 13:34 GMT

> I need a regular expression - it should:
>
> Allow all Strings that do not begin with "car_"

Why reqex for that?

!s.startsWith("car_")

piotr

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Christine Mayer - 15 Oct 2007 14:01 GMT

> Why reqex for that?
>
> !s.startsWith("car_")
>
> piotr

Because I am using http://tuckey.org/urlrewrite/

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Piotr Kobzda - 15 Oct 2007 14:37 GMT

>> Why reqex for that?

> Because I am using http://tuckey.org/urlrewrite/

OK, I asked because people sometimes uses regex without a real need for
that. In your case, it seems there is no other way... So, refer to the
Gordon's response, or try the following:

"(?!car_)(?s).*"

piotr

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Ingo Menger - 15 Oct 2007 13:56 GMT

> Hi,
>
> I need a regular expression - it should:
>
> Allow all Strings that do not begin with "car_"

[stuff deleted]

> Any idea how to fix that?

Sometimes it is possible to reformulate the problem:

"For all strings that do not begin with 'car_' do X"
==>
"For all strings do if it begins with 'car_' then nothing else X"

Reply to this Message

Tim Smith - 16 Oct 2007 05:25 GMT

> I need a regular expression - it should:
>
> Allow all Strings that do not begin with "car_"

^([^c]|c[^a]|ca[^r]|car[^_])

Signature

--Tim Smith

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regular expression

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