using System;

using System.Text.RegularExpressions;

using System.Text;

​

public class Program

{

    public static void Main(string[]args)

    {

        var s = "a \nb" + Convert.ToString((char)0x1b) + Convert.ToString((char) 0x1e);

        byte[] ba = Encoding.Default.GetBytes(s);

        Console.WriteLine(s);

        Console.WriteLine(BitConverter.ToString(ba));

        Console.WriteLine();

​

        var lines = s.Split(new[] { Environment.NewLine }, StringSplitOptions.None);

        var sb = new StringBuilder();

​

        foreach (var line in lines)

        {

            sb.AppendLine(Regex.Replace(line, @"\p{C}+", String.Empty));

        }

        if (sb[sb.Length - 1] == '\n')

            sb.Remove(sb.Length - 1, 1);

        s = sb.ToString();

        Console.WriteLine(s);

        ba = Encoding.Default.GetBytes(s);

        Console.WriteLine(BitConverter.ToString(ba));

    }

}