c# - regex checking time -

i've got following regex:

^(?:(?:([01]?\d|2[0-3]):)?([0-5]?\d):)?([0-5]?\d)$ 

this accept 00:00:00 or 00:00 or 00 don't want this. can accept 00:01 or 00:00:01 not zeros.

what have missed in regex?

you can use negative lookaheads solve this:

^(?!^(\d|0)*$)(?:(?:([01]?\d|2[0-3]):)?([0-5]?\d):)?([0-5]?\d)$ 

the negative lookahead matches nondigits , zeroes. if have zeroes in time, fail match.

you can see in more detail on www.debuggex.com.