Question

I have the following simple test which doesnt return true for some reason.

string[] test = new string[] { "A", " ", " ", "D", "" };
Regex reg = new Regex(@"^[A-Z]\s$");
bool ok = test.All(x => reg.IsMatch(x));

I’ve also tried putting the \s inside the square brackets but that doesn’t work either

I want to make sure that all characters in the array that are not empty or blank spaces match A-Z.

I realise I could do a Where(x=>!String.IsNullorEmpty(x) && x != ” “) before the All but I thought Regex could handle this scenario

Answer 1

I think you want:

Regex reg = new Regex(@"^[A-Z\s]*$");

That basically says “the string consists entirely of whitespace or A-Z”.

If you want to force it to be a single character or empty, just change it to:

Regex reg = new Regex(@"^[A-Z\s]?$");