using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        const string ReferencePattern = @"^(\w+)$";

        const string reference = "你好";

        var x = Regex.Match(reference, ReferencePattern);

        if (!x.Success)

        {

            Console.WriteLine("No matches!");

        }

        else

        {

            Console.WriteLine($"Found a match: {x.Groups[1].Value}");

        }

    }

}