Time regex issue

Question

I want to return the time format HH:MM am|pm (11:45 AM) or any time matches this regex :

    String meridian = "^(0[1-9]|[10-12]):(0[1-9]|[11-59])\\s(AM|PM|am|pm)";

But its not working for me.

[10-12] and [11-59] do not mean what you think they do. The - in a character group doesn't work for two-digit numbers, so [11-59], means a 1 or 1-5 or 9. — mellamokb
– mellamokb, Commented Jul 20, 2012 at 13:44
Why do you want to use regular expressions rather than simply trying to parse the value? — Jon Skeet
– Jon Skeet, Commented Jul 20, 2012 at 13:45

codaddict · Accepted Answer · 2012-07-20 13:46:24Z

4

[10-12] is equivalent to [1012] which is equivalent to [012]

Similarly [11-59] is equivalent to [123459]

Use:

^(0[0-9]|1[0-2]):[0-5][0-9]\\s(AM|PM|am|pm)$

answered Jul 20, 2012 at 13:46

codaddict

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1 Comment

how to modify the regex then ?

Dennis · Accepted Answer · 2012-07-20 13:48:26Z

1

[...] is a set of characters, not numbers.

To match all numbers between 01 and 12, use (0[1-9]|1[0-2]).

To match all numbers between 00 and 59, use [0-5][0-9]

answered Jul 20, 2012 at 13:48

Dennis

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