using System;using System.Text;using System.Diagnostics;using System.Collections.Generic;using System.Text.RegularExpressions;

public static class Program

{

    //https://unicode-table.com/en/blocks/general-punctuation/ add some special cases

    public static bool isSpecialUnicodeCntrlChr(this Char c)

    {

        //remove left-to-rights and right-to-lefts

        switch (c)

        {

            case '\u200E': //Left-To-Right Mark

            case '\u200F': //Right-To-Left Mark

            case '\u202A': //Left-To-Right Embedding

            case '\u202B': //Right-To-Left Embedding

            case '\u202D': //Left-To-Right Override

            case '\u202E': //Right-To-Left Override

            case '\u2066': //Left-To-Right Isolate

            case '\u2067': //Right-To-Left Isolate

            //https://unicode-table.com/en/blocks/general-punctuation/ add more 

            //case '\u2060': //Word Joiner

            //etc....   

                return true; 

            default:

                return false;

        }

    }

    public static string RemoveUnicodeControlChars(this string s) {

        StringBuilder sb = new StringBuilder(s.Length);

        for (int i = 0; i < s.Length; i++) 

            if ( !Char.IsControl(s[i]) && !s[i].isSpecialUnicodeCntrlChr() )

                sb.Append(s[i]);

        return sb.ToString(); 

    }

    // create a lookup hashset

    private static HashSet<char> specialUnicodeCtrlChr = new HashSet<char>(new char[] {'\u200E','\u200F','\u202A','\u202B','\u202D','\u202E', '\u2066', '\u2067'} );

​

    public static string FilterUnicodeControlChars(this string str)

    {

        // tempbuffer

        char[] buffer = new char[str.Length];

        int index = 0;

​

        // check each character

        foreach (var ch in str)

            if ( !Char.IsControl(ch) && !specialUnicodeCtrlChr.Contains(ch))

                buffer[index++] = ch;

​

        // return the new string.

        return new String(buffer, 0, index);

    }

    //speed optimization

    const string pattern = @"\p{C}";

    const RegexOptions options = RegexOptions.Multiline;

    private static readonly Regex regRemoveAllUni = new Regex(pattern, options);

​

    public static void Main()

    {

        Stopwatch sw = new Stopwatch(); 

        Console.WriteLine("Hungarian\bGrand\t\t\r\vPrix\u202EF1");

        sw.Start();

        Console.Write("Hungarian\bGrand\t\t\r\vPrix\u202EF1".RemoveUnicodeControlChars());

        sw.Stop(); 

        Console.WriteLine(" in {0} ticks.",sw.ElapsedTicks );

        Console.WriteLine();

        sw.Reset();

        sw.Start();

        Console.WriteLine("ŐhᢰHung\u2063arian\u008D\bGrand\t\t\r\vPrix\u202EF1".RemoveUnicodeControlChars());

        sw.Stop(); 

        Console.WriteLine(" in {0} ticks.",sw.ElapsedTicks );

        Console.WriteLine();

        Console.WriteLine();

        Console.WriteLine("Using HashSet Filtering");

        sw.Start();

        Console.Write("Hungarian\bGrand\t\t\r\vPrix\u202EF1".FilterUnicodeControlChars());

        sw.Stop(); 

        Console.WriteLine(" in {0} ticks.",sw.ElapsedTicks );

        Console.WriteLine();

        sw.Reset();

        sw.Start();

        Console.WriteLine("ŐhᢰHung\u2063arian\u008D\bGrand\t\t\r\vPrix\u202EF1".FilterUnicodeControlChars());

        sw.Stop(); 

        Console.WriteLine(" in {0} ticks.",sw.ElapsedTicks );

​

        //TO REMOVE ALL UNICODE TEXT PROPERLY //Thu 21-Nov-24 11:35pm EST MDC - 

​

        sw.Start();

        Console.WriteLine("\n\nUnicode Regex to remove all Control chars"); 

        Console.WriteLine(regRemoveAllUni.Replace("ŐhᢰHung\u2063arian\u008D\bGrand\t\t\r\vPrix\u202EF1", ""));

        sw.Stop(); 

        Console.WriteLine(" in {0} ticks.",sw.ElapsedTicks );

​

    }

}