regex - Need a regular expression - disallow all zeros

Question

I want to validate a string to meet the following conditions:

• Must be 6 characters long
• Only the first character can be alpha-numeric the rest must be numeric
• If first digit is alpha, it must be caps
• Can't be all zeros

I have the following regular expression that gets everything except the all zeros part. Is there a way to disallow all zeros?

^[A-Z0-9][0-9]{5}$

Is the only way to do this to check the regex (and allow "000000") but then check specifically that it's not "000000"?

Thanks.

Answer 1

Just have a negative lookahead like this to disallow all 0s:

/^(?!0{6})[A-Z0-9][0-9]{5}$/