Regex help

[Leon Mayne]

I'm trying to add a regex validator to a webform textbox to validate time
format. The field is optional, so I'm trying to get a regex which will
validate empty, or the format
[00-23]:[00-59]
Is anyone here good with regular expressions and can point me to a pattern
that will do the above?

 

[Alexey Smirnov]

I'm trying to add a regex validator to a webform textbox to validate time
format. The field is optional, so I'm trying to get a regex which will
validate empty, or the format
[00-23]:[00-59]
Is anyone here good with regular expressions and can point me to a pattern
that will do the above?

try

\[\d\d-\d\d\]:\[\d\d-\d\d\]

 

[Leon Mayne]

\[\d\d-\d\d\]:\[\d\d-\d\d\]

Hmm, won't that show 99:99 as valid, and an empty string as invalid?

 

[Leon Mayne]

I'm trying to add a regex validator to a webform textbox to validate time
format. The field is optional, so I'm trying to get a regex which will
validate empty, or the format
[00-23]:[00-59]
Is anyone here good with regular expressions and can point me to a pattern
that will do the above?

Oh wait, I think I've got it.
Would:
(0[0-9]|1[0-9]|2[0-3])0[0-9]|[0-5][0-9])
Work?

 

[Alexey Smirnov]

\[\d\d-\d\d\]:\[\d\d-\d\d\]

Hmm, won't that show 99:99 as valid,

you're right, but then you should extend your validation expression

e.g.

\[[0|1|2][0|1|2|3]-[0|1|2][0|1|2|3]]......

to match

[00-01]...,
[22-23]...

but not

[24-25]...,
etc

and an empty string as invalid?

RegularExpressionValidator won't fire when input is empty. When you
want to disallow an empty string, you should add the
RequiredFieldValidator Control.

 

[Leon Mayne]

you're right, but then you should extend your validation expression

Yes, I think I've compressed my original one down now:
([0-1][0-9]|2[0-3])[0-5][0-9])
Does that look right?

RegularExpressionValidator won't fire when input is empty

True, I forgot about that.

Thanks for your help

 

[Alexey Smirnov]

you're right, but then you should extend your validation expression

Yes, I think I've compressed my original one down now:
([0-1][0-9]|2[0-3])[0-5][0-9])
Does that look right?

No.

The logic is very simple. The brackets [] denote a number range.

[0|1|2] indicates that we are looking for 0, 1, or 2
[0|1|2|3] indicates that we are looking for 0, 1, 2, or 3

so, [0|1|2][0|1|2|3] will validate 00, 01, 02 .. 23, but not 24, 25
etc.

So, to validate "[00-23]:[00-59]" you would need something like the
following string

\[[0|1|2][0|1|2|3]-[0|1|2][0|1|2|3]\]:\[[0|1|2|3|4|5][0|1|2|3|4|5|6|7|
8|9]-[0|1|2|3|4|5][0|1|2|3|4|5|6|7|8|9]\]

Hope this helps

 

[Leon Mayne]

Yes, I think I've compressed my original one down now:
([0-1][0-9]|2[0-3])[0-5][0-9])
Does that look right?

No
The logic is very simple. The brackets [] denote a number range.
[0|1|2] indicates that we are looking for 0, 1, or 2
[0|1|2|3] indicates that we are looking for 0, 1, 2, or 3
so, [0|1|2][0|1|2|3] will validate 00, 01, 02 .. 23, but not 24, 25
etc.

So, to validate "[00-23]:[00-59]" you would need something like the
following string

\[[0|1|2][0|1|2|3]-[0|1|2][0|1|2|3]\]:\[[0|1|2|3|4|5][0|1|2|3|4|5|6|7|
8|9]-[0|1|2|3|4|5][0|1|2|3|4|5|6|7|8|9]\]

What's the difference between [0|1|2|3|4|5|6|7|8|9] and [0-9]?

 

[Alexey Smirnov]

Yes, I think I've compressed my original one down now:
([0-1][0-9]|2[0-3])[0-5][0-9])
Does that look right?

No
The logic is very simple. The brackets [] denote a number range.
[0|1|2] indicates that we are looking for 0, 1, or 2
[0|1|2|3] indicates that we are looking for 0, 1, 2, or 3
so, [0|1|2][0|1|2|3] will validate 00, 01, 02 .. 23, but not 24, 25
etc.

So, to validate "[00-23]:[00-59]" you would need something like the
following string

\[[0|1|2][0|1|2|3]-[0|1|2][0|1|2|3]\]:\[[0|1|2|3|4|5][0|1|2|3|4|5|6|7|
8|9]-[0|1|2|3|4|5][0|1|2|3|4|5|6|7|8|9]\]

What's the difference between [0|1|2|3|4|5|6|7|8|9] and [0-9]?- Hide quoted text -

- Show quoted text -

Hi Leon

Sorry I think you're right and I did a mistake in my answer. The
syntax for the regular-expression validation controls is a little bit
different than on the server and so, it's always better to validate
each expression using a validator control (I thought 0-9 will not work
there). Please refer to http://msdn2.microsoft.com/en-us/library/ae5bf541.aspx.
So, if you want to validate a regular 24hr time input string then you
expression will work.

Note, "[0-9]" equivalent to "\d"

 

[Leon Mayne]

Note, "[0-9]" equivalent to "\d"

Good point, so it could be:

([0-1]\d|2[0-3])[0-5]\d)

 

[Jesse Houwing]

Hello Alexey,

m...

Yes, I think I've compressed my original one down now:
([0-1][0-9]|2[0-3])[0-5][0-9])
Does that look right?
No
The logic is very simple. The brackets [] denote a number range.
[0|1|2] indicates that we are looking for 0, 1, or 2
[0|1|2|3] indicates that we are looking for 0, 1, 2, or 3
so, [0|1|2][0|1|2|3] will validate 00, 01, 02 .. 23, but not 24, 25
etc.
So, to validate "[00-23]:[00-59]" you would need something like the
following string

\[[0|1|2][0|1|2|3]-[0|1|2][0|1|2|3]\]:\[[0|1|2|3|4|5][0|1|2|3|4|5|6|
7| 8|9]-[0|1|2|3|4|5][0|1|2|3|4|5|6|7|8|9]\]

What's the difference between [0|1|2|3|4|5|6|7|8|9] and [0-9]?- Hide
quoted text -

- Show quoted text -

Hi Leon

Sorry I think you're right and I did a mistake in my answer. The
syntax for the regular-expression validation controls is a little bit
different than on the server and so, it's always better to validate
each expression using a validator control (I thought 0-9 will not work
there). Please refer to
http://msdn2.microsoft.com/en-us/library/ae5bf541.aspx.
So, if you want to validate a regular 24hr time input string then you
expression will work.
Note, "[0-9]" equivalent to "\d"

As a side note:
[0123456789] equals [0-9]
but [0|1|2|3|4|5|6|7|8|9|0] equals [0-9|] you should not use the | within
a range.

Another note, the clientside and serverside validations are almost equal.
A few specifics in substracting ranges from an existing group and look behinds
are all that differentiate them. You can find the exact info on http://www.regular-expressions.info/refflavors.html