c# - regex check for white space in middle of string

Question

I want to validate that the characters are alpha numeric:

Regex aNum = Regex("[a-z][A-Z][0-9]");

I want to add the option that there might be a white space, so it would be a two word expression:

Regex aNum = Regex("[a-z][A-Z][0-9]["\s]");

but couldn't find the correct syntax.

id applicate any incite.

Answer 1

[A-Za-z0-9s]{1,} should work for you. It matches any string which contains alphanumeric or whitespace characters and is at least one char long. If you accept underscores, too you shorten it to [ws]{1,}.

You should add ^ and $ to verify the whole string matches and not only a part of the string:

^[A-Za-z0-9s]{1,}$ or ^[ws]{1,}$.