[RESOLVED] XOR'ing in C#

[dr_aybyd]

Hi I need little help here

Here is my given string "8f43ae1a3319c649cc57408b6a392d6b"

8f xor 33 xor cc xor 6a =1a
43 xor 19 xor 57 xor 39 =34
ae xor c6 xor 40 xor 2d =05
1a xor 49 xor 8b xor 6b =b3

1a3405b3 and 1ffffff or 2000000 = 23405B3


How to apply that using C#?

[stlaural]

Hi, Try this, it should help you get going. What I did is I used regular expressions to split your input string and then I used two FOR loops to get the values the same way you posted.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Text.RegularExpressions;
 
 
namespace test
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
 
        private void button1_Click(object sender, EventArgs e)
        {
            byte[] valuearray = new byte[4];
            string s = "8f43ae1a3319c649cc57408b6a392d6b";
            Regex rx = new Regex(@"\w{2}");
            MatchCollection mc = rx.Matches(s);
 
 
            int n = mc.Count / 4;
            for (int i = 0; i < n; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    valuearray[j] = Convert.ToByte(mc[i + (j * n)].Value, 16);
                }
                int value = valuearray[0] ^ valuearray[1] ^ valuearray[2] ^ valuearray[3];
                MessageBox.Show(value.ToString("X2"));
            }               
        }
    }
}

I didn't do that part though :

1a3405b3 and 1ffffff or 2000000 = 23405B3

as I don't know where you got the last 2 values from, but I think you should be able to figure it out with the sample I posted.

I hope this helps you.

[dr_aybyd]

It works
BTW I modify some to suite my needs thanks.

private void button2_Click(object sender, EventArgs e)
        {
            byte[] valuearray = new byte[4];
            string s = "8f43ae1a3319c649cc57408b6a392d6b";
            Regex rx = new Regex(@"\w{2}");
            MatchCollection mc = rx.Matches(s);
            StringBuilder sb = new StringBuilder();

            int n = mc.Count / 4;
            for (int i = 0; i < n; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    valuearray[j] = Convert.ToByte(mc[i + (j * n)].Value, 16);
                }
                int value = valuearray[0] ^ valuearray[1] ^ valuearray[2] ^ valuearray[3];
                
                sb.Append(value.ToString("X2"));
                textBox3.Text = sb.ToString();

            }
        }

1a3405b3 and 1ffffff or 2000000 = 23405B3

green color is the result of that xor
I need to AND and OR to that value to get some codes in red color

[stlaural]

Oh I see, its all about color. I was wondering.

Glad you got it working.

[dr_aybyd]

I got it all works
thanks stlaural
Here is my final codes

private void button2_Click(object sender, EventArgs e)
        {
            byte[] valuearray = new byte[4];
            string s = "8f43ae1a3319c649cc57408b6a392d6b";
            Regex rx = new Regex(@"\w{2}");
            MatchCollection mc = rx.Matches(s);
            StringBuilder sb = new StringBuilder();
 
            int n = mc.Count / 4;
            for (int i = 0; i < n; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    valuearray[j] = Convert.ToByte(mc[i + (j * n)].Value, 16);
                }
                int value = valuearray[0] ^ valuearray[1] ^ valuearray[2] ^ valuearray[3];
 
                sb.Append(value.ToString("X2"));
                textBox3.Text = sb.ToString();
                int myCodes = (0x1a3405b3 & 0x1ffffff) | 0x2000000;
                string newCodes = myCodes.ToString("X2");
 
                String hexNumber = newCodes;
                int hextodecs = Int32.Parse(hexNumber, NumberStyles.HexNumber);
                //MessageBox.Show(i.ToString());
 
 
                textBox4.Text = hextodecs.ToString();
            }
        }