Question

I know this might be a novice question regarding Regex in general but I hope someone can help. I need a reg expression that accepts 0-3 digits numbers + zero or 1 occurence of the character “:” or “.” + 0-2 digit number. Also there should be no other characters allowed

The user can then input valid numbers like

100:,
:0, 
:, 
1, 
10.6, 
111:11

Thanks in advance.

Answer 1

You could use

^\d{0,3}([:\.]\d{0,2})?$

The part \d{0,3} matches zero to three digits, the part [:\.]\d{0,2} matches a : or ., followed by up to two digits, the braces with the ? make this part optional. ^ and $ anchor the expression at the start and end of the string.

See it in action at http://regexr.com?31tqd