Question

I want to check in a C# program, if a user input is a single word. The word my only have characters A-Z and a-z. No spaces or other characters.
I try [A-Za-z]* , but this doesn’t work. What is wrong with this expression?

Regex regex = new Regex("[A-Za-z]*");
if (!regex.IsMatch(userinput);)
{
  ...
}

Can you recomend website with a comprensiv list of regex examples?!

Answer 1

It probably works, but you aren’t anchoring the regular expression. You need to use ^ and $ to anchor the expression to the beginning and end of the string, respectively:

Regex regex = new Regex("^[A-Za-z]+$");

I’ve also changed * to + because * will match 0 or more times while + will match 1 or more times.