Regular Expression for Multi Date format

Tea_J

Hi guys..

I can't seem to figure out the right reg exp for atleast 2 date formats..

well, actually one format but allowing 2 delimiters...

"-" and "/"

the regexp i have is the regular stuff:

\d{4}-\d{2}-\d{2}

matching ....
YYYY-MM-DD

Any ideas?

tea

PS
I noticed that with the above regexp, the first set of decimal (YYYY) can be more than or less than 4 characters and it would still return a match, even though i specified {4} already.

pkemper

I'm not sure what your application is for these date conversions (I guess conversion from SQL date format to US date format).

Why not use the DATE_FORMAT option in SQL to return properly formated dates.

As for a date regexp, you need to know what delimiter character was used in order to put the day, month and year back into the proper order.

If people can enter dates in your web form, then a check might need to include the following formats:
YYYY-MM-DD
YY-MM-DD
MM/DD/YY
MM/DD/YYYY
M/D/YY
M/D/YYYY
and even (for international users)
D-MM-YYYY
DD.MM.YY
DD.MM.YYYY
YYYY.MM.DD
MM😃D:YY
MM😃D:YYYY

This becomes very cumbersome.

Tea_J

umm. dude.. you're way off.. lolz

i just need a regexp that would allow 2 delimiters...

perhaps the title of my thread is misleading.. but my post explains it all. 🙂

I'm not even into database entry yet with this one.. this is just a simple USER INPUT check..

The format for date is

YYYY-MM-DD or YYYY/MM/DD

pkemper

And are you sure users will really just type what you think they will type?

Tea_J

And are you sure users will really just type what you think they will type?

huh??

dude i dont think you're getting the point here..

1) In my form i have instructed that they enter the date in the said format..

2) I have javascript in place to check if they complied to that..

3) my PHP script should check also if it is really IN THE FORMATS I WANT IT, and THE FORMAT AS INSTRUCTED..

Now, my dilema is the php side, i can't figure out the right regular expression for checking it..

tea

pkemper

Does this work:

"^{[0-9]{4}([-/][0-9]{2}){2}$"}

Tea_J

nope.. returned errors dude.. thanks anyway..

I FIGURED IT OUT!!! yepee 😃

pattern to allow YYYY-MM-DD and YYYY/MM/DD format should be

\d{4}(\/|-)\d{2}(\/|-)\d{2}

what i've been trying is similar but can't seem to get it to work because it looked like this:

\d{4}(/|-)\d{2}(/|-)\d{2}

basically, stupid me forgot to ESCAPE the "/" character as delimiter.. lolz

whew.. glad that's out of the way.

thanks

xblue

Hi,

just some additional suggestions: to avoid having to escape the slash within the pattern, you can just as well use e.g. # or § or anything.

then, backreferences could be employed to make sure both separators are identic, rejecting invalid YYYY/MM-DD, like
[pre]
\d{4}(/|-)\d{2}\1\d{2}
[/pre]