.Net multi-lingual IsAlphaNumeric API

I have made a multi lingual extension API for string which can identify if a string (in different languages) is AlphaNumeric. The API uses Regular Expression support for Unicode.

IsAlphaNumeric - String must contain atleast 1 alpha (letter in Unicode range, specified in charSet) and atleast 1 number (specified in numSet). Also, the string should comprise only of alpha and numbers.

The charSet/numSet Unicode range for the desired language can be specified. The Unicode ranges are available on below link:

http://www.ssec.wisc.edu/~tomw/java/unicode.html

API:

public static class Extension
{
    public static bool IsAlphaNumeric(this string stringToTest)
    {
        //English
        const string charSet = "a-zA-Z";
        const string numSet = @"0-9";

        //Greek
        //const string charSet = @"\u0386\u0388-\u03F3";
        //const string numSet = @"0-9";

        //Bengali
        //const string charSet = @"\u0985-\u09E3";
        //const string numSet = @"\u09E6-\u09EF";

        //Hindi
        //const string charSet = @"\u0905-\u0963";
        //const string numSet = @"\u0966-\u096F";

        //Japanese Hiragana
        //const string charSet = @"\u3041-\u3094";
        //const string numSet = @"0-9";

        //Hebrew
        //const string charSet = @"\u05D0-\u05EA";
        //const string numSet = @"0-9";

        //Latin basic and Supplement. German, French etc.
        //const string charSet = @"a-zA-Z\u00C0-\u00FF";
        //const string numSet = @"0-9";

        return Regex.Match(stringToTest, @"^(?=[" + numSet + @"]*?[" + charSet + @"]+)(?=[" + charSet + @"]*?[" + numSet + @"]+)[" + charSet + numSet + @"]+$").Success;
    }
}

Usage: