Useful Regular Expression for a UserName
^[a-zA-Z0-9_\.\-]+$
Allows only Alphanumeric characters with a period(.), Underscore(_) and a Hyphen (-). No spaces or other characters allowed.
Categories: ASP .NET, Web Development
Alphanumeric, Fullstop, Hyphen, no spaces, Period, Regex, regular expressions, Underscore, UserName
