Regex parsing "^[a-zA-Z0-9]{5,20}+$" - Nested quantifier +

Unity Engine
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1

Hi,
I’m trying to use regex:

if (!Regex.Match(name, "^[a-zA-Z0-9]{5,20}+$").Success)

However, it gives error: ArgumentException: parsing "^[a-zA-Z0-9]{5,20}+$" - Nested quantifier +.

When trying to escape +:
if (!Regex.Match(name, "^[a-zA-Z0-9]{5,20}//+$").Success)
it is not working - no error, but every string is invalid.

Please help.

2

You need to surround the expression you want to use the + symbol on with parentheses like this:

^([a-zA-Z0-9]{5,20})+$

Here’s a version of it modified to look for whitespace in case you’re trying to support multiple words:

^([a-zA-Z0-9]{5,20}[\s]{0,1})+$

For debugging regular expressions I recommend the following site:

1 Like
3

Thank you very much!