using System;

using System.Text;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        //string text = "Baden-Württemberg";

        string text = "ü";//"ō";

        Console.WriteLine("Hello World: {0}", IsASCII(text));

    }

    public static bool IsASCII(string value)

        {

            // ASCII encoding replaces non-ascii with question marks, so we use UTF8 to see if multi-byte sequences are there

            Console.WriteLine("ASCII Bytes: {0}", Encoding.ASCII.GetBytes(value));

            //Console.WriteLine("ASCII Bytes Count: {0}", Encoding.ASCII.GetString(value));

            Console.WriteLine("Value Length: {0}", value.Length);

            Console.WriteLine("sOut: {0}", Encoding.ASCII.GetString(Encoding.ASCII.GetBytes(value)));

            Console.WriteLine("Regex replaced {0}", Regex.Replace(value, @"[^\u0020-\u00FF]+", string.Empty));

            var regexItem = new Regex("[\u0020-\u00FF]+");

            return regexItem.IsMatch(value);

            //return Encoding.ASCII.GetByteCount(value) == value.Length;

        }

}