using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        var x = new Regex(@"[^\p{L}\d]");

        MatchTest(ref x, "Bananas12345");

        MatchTest(ref x, @"..\../..\https://www.badsite.com/bad%20path/x?y=z#badplace");

        MatchTest(ref x, "Àâãäåæçèéêëìíîïðñòóôõøùúûüýþÿı");     // Lots of accents

        MatchTest(ref x, "¢¬¶À");               // Odd characters

        MatchTest(ref x, "速速上手上手で");        // Japanese

        MatchTest(ref x, "假借字转注字轉注字");              // Chinese

        MatchTest(ref x, "احتاجاناتدربعلىالعربية");             // Arabic

    }

    private static void MatchTest(ref Regex x, string test)

    {

        if (!x.IsMatch(test))

            Console.WriteLine(test + ":OK");

        else

        {

            Console.WriteLine(test + ":failed. Cleaned:" + x.Replace(test,""));

        }

    }

}