RegularExpressionValidator returns false for valid input

Question

I am trying to validate time zone offset which has the format of optional minus sign, followed by two digits, followed by colon followed by two more digits; like -05:00 or 04:30. I used \\b[-]?\\d{2}:\\d{2}\\b as validation expression, tested it on some online RE testing sites and I get "Successful Match" but validator keeps returning falase. I can't see what I am doing wrong. I enter -05:00 or -13:99 and they both return false. I tried to escape the colon but same thing.

Answer 1

Drop the word boundaries then you'll get your matches.

-?\d{2}:\d{2} 

If you only want the first occurrence then make it like this:

-?\d{2}:\d{2}$

If you only want to match valid times use this one:

-?([0-2][0-3]|[0-1][0-9]):([0-5][0-9])

The above one matches any hour in the range of 0-23:0-59 btw.