My co-worker came up with a regex that validate dates... and it even validates leap years!

Sentenryu

please, tell me this has a bug:

"^(((0[1-9]|[12]\\d|3[01])\\/(0[13578]|1[02])\\/((19|[2-9]\\d)\\d{2}))|((0[1-9]|[12]\\d|30)\\/(0[13456789]|1[012])\\/((19|[2-9]\\d)\\d{2}))|((0[1-9]|1\\d|2[0-8])\\/02\\/((19|[2-9]\\d)\\d{2}))|(29\\/02\\/((1[6-9]|[2-9]\\d)(0[48]|[2468][048]|[13579][26])|((16|[2468][048]|[3579][26])00))))$"

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)

Thomas Daniels

That's a very long expression. This is a shorter expression that validate dates:

^\d{4}[- /.](0?[1-9]|1[0-2])[- /.](0?[1-9]|[12][1-9]|3[01])$

Expresso[^] is a good tool to create regular expressions.

In some cases, my signature will be longer than my message...

ProgramFOX

ProgramFOX

Sentenryu

thanks for the reply, we actually found a bug on that expression when entering 01/01/2013 (dd/MM/yyyy), for some reason, this value was rejected...

I'm brazilian and english (well, human languages in general) aren't my best skill, so, sorry by my english. (if you want we can speak in C# or VB.Net =p)

Thomas Daniels

Sentenryu wrote:

thanks for the reply

You're welcome!

Sentenryu wrote:

dd/MM/yyyy

My expression is for yyyy/MM/dd. An expression for dd/MM/yyyy:

^(0?[1-9]|[12][1-9]|3[01])[- /.](0?[1-9]|1[0-2])[- /.]\d{4}$

In some cases, my signature will be longer than my message...

ProgramFOX

ProgramFOX

pt1401

Its much shorter yes, but it's overly simplistic. It says 31st Feb is a valid date :(

Thomas Daniels

There's a difference between a valid date and a valid date format. A regex is good for checking formats, but I don't think it works for checking whether a day exists.

In some cases, my signature will be longer than my message...

ProgramFOX

ProgramFOX

Lutoslaw

Maybe it checks if you have to go to work too. AFAIK 1.1 is work-free.

Greetings - Jacek