How to verify date format using regular expression?

Question

How to verify below format using regular expression in c#.. can you help me..

Today's Date: 03:30 AM ET, 02/15/2013

I used below format but its not working..

@"^ Today's Date: (\d{2})(\:)(\d{2})$ AM ET, ^(0[1-9]|[12][0-9]|3[01])[- /.](0[1-9]|1[012])[- /.](19|20)\d\d$"

C# or Java? Which one? And will your date always be in this format? How about `PM`? — Rohit Jain, Feb 15 '13 at 08:56

score 0 · Answer 1 · edited May 23 '17 at 10:32

It looks like there are 3 problems with your regular expression:

There is a leading space between ^ and T of Today's
the portions of your regular expression for matching the day and the month are in the wrong order
The $ and ^ midway through the expression shouldn't be there

(0[1-9]|[12][0-9]|3[01]) matches 01 to 31 and (0[1-9]|1[012]) matches 01 to 12

making the corrected pattern:

^Today's Date: (\d{2})(\:)(\d{2}) AM ET, (0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])[- /.](19|20)\d\d$

But as Rahul R. says in the comments, using a proper date parsing method is probably the way to go.

score 0 · Answer 2 · answered Feb 15 '13 at 09:29

0

Use this:

^Today's Date: ([01][0-9]|[2[0-3]):([0-5][0-9]) [AP]M ET, ((0[1-9]|[12][0-9]|3[01])/(?=(0[13578]|1[02]))(0[13578]|1[02])|(0[1-9]|[12][0-9]|30)/(?=(0[469]|11))(0[469]|11)|(0[1-9]|[12][0-9])/(?=(02))(02))/(0{3}[1-9]|((?!0{3}\d)\d{4}))$

answered Feb 15 '13 at 09:29

Naveed S

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The below code is working fine for me ,@"^Today's Date: (\d{2})(\:)(\d{2}) [AP]M ET, (\d{2})(\/)(\d{2})(\/)(\d{4})$" thanks for help.... – saran Feb 15 '13 at 09:39
@saran but it allows 99:99 AM ET, 33/44/5555 – Naveed S Feb 15 '13 at 09:43

How to verify date format using regular expression?

2 Answers2