using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    class HexRTBTest : RichTextBox
    {
        private const string rtf_header = @"{\rtf1\fbidis\ansi\ansicpg1252\deff0\deflang2057{\fonttbl{\f0\fmodern\fprq1\fcharset0 Courier New;}{\f1\fnil\fcharset0 Microsoft Sans Serif;}}";
        private const string rtf_color_table = @"{\colortbl ;\red255\green255\blue255;}";
        private const string rtf_footer = @"\pard\ltrpar\f1\fs17\par}";

        private List<HexRTBRow> rows = new List<HexRTBRow>();

        public HexRTBTest()
        {
            this.MinimumSize = new Size(368, 0);
            this.ScrollBars = RichTextBoxScrollBars.ForcedVertical;
            this.WordWrap = false;
        }

        public void AddRow(HexRTBRow item)
        {
            this.rows.Add(item);
            this.DrawResults();
        }

        public void AddRows(HexRTBRow[] items)
        {
            this.rows.AddRange(items);
            this.DrawResults();
        }

        // you could add other methods like InsertRow, RemoveRow and so on...

        private void DrawResults()
        {
            this.Clear();

            if (rows.Count == 0)
                return;
            
            StringBuilder sb = new StringBuilder();
            sb.AppendLine(rtf_header);
            sb.AppendLine(rtf_color_table);

            for (int i = 0; i < rows.Count; i++)
            {
                if (i == 0)
                {
                    sb.Append(@"\viewkind4\uc1\trowd\trgaph108\trleft-108\trbrdrt\brdrs\brdrw10\brdrcf1 ");
                    sb.Append(@"\trbrdrl\brdrs\brdrw10\brdrcf1 \trbrdrb\brdrs\brdrw10\brdrcf1 \trbrdrr\brdrs\brdrw10\brdrcf1 ");
                    sb.Append(@"\clbrdrt\brdrw15\brdrs\clbrdrl\brdrw15\brdrs\clbrdrb\brdrw15\brdrs\clbrdrr\brdrw15\brdrs ");
                    sb.Append(@"\cellx709\clbrdrt\brdrw15\brdrs\clbrdrl\brdrw15\brdrs\clbrdrb\brdrw15\brdrs\clbrdrr\brdrw15\brdrs ");
                    sb.Append(@"\cellx3828\clbrdrt\brdrw15\brdrs\clbrdrl\brdrw15\brdrs\clbrdrb\brdrw15\brdrs\clbrdrr\brdrw15\brdrs ");
                    sb.Append(@"\cellx5103\pard\intbl\ltrpar\f0\fs20 ");
                    sb.AppendLine(rows[i].column1 + "\\cell " + rows[i].column2 + "\\cell " + rows[i].column3 + "\\cell\\row");
                }
                else
                {
                    sb.Append(@"\trowd\trgaph108\trleft-108\trbrdrt\brdrs\brdrw10\brdrcf1 ");
                    sb.Append(@"\trbrdrl\brdrs\brdrw10\brdrcf1 \trbrdrb\brdrs\brdrw10\brdrcf1 ");
                    sb.Append(@"\trbrdrr\brdrs\brdrw10\brdrcf1 \clbrdrt\brdrw15\brdrs\clbrdrl\brdrw15\brdrs\clbrdrb\brdrw15");
                    sb.Append(@"\brdrs\clbrdrr\brdrw15\brdrs \cellx709\clbrdrt\brdrw15\brdrs\clbrdrl\brdrw15\brdrs\clbrdrb");
                    sb.Append(@"\brdrw15\brdrs\clbrdrr\brdrw15\brdrs \cellx3828\clbrdrt\brdrw15\brdrs\clbrdrl\brdrw15\brdrs");
                    sb.Append(@"\clbrdrb\brdrw15\brdrs\clbrdrr\brdrw15\brdrs \cellx5103\intbl ");
                    sb.AppendLine(rows[i].column1 + "\\cell " + rows[i].column2 + "\\cell " + rows[i].column3 + "\\cell\\row");
                }
            }

            sb.AppendLine(rtf_footer);
            this.Rtf = sb.ToString();
            this.SelectionStart = this.Text.Length;
        }
    }

    class HexRTBRow
    {
        public string column1;
        public string column2;
        public string column3;

        public HexRTBRow() { }

        public HexRTBRow(string column1, string column2, string column3)
        {
            this.column1 = column1;
            this.column2 = column2;
            this.column3 = column3;
        }

        public override bool Equals(object obj)
        {
            HexRTBRow blah = (HexRTBRow)obj;
            return this.column1 == blah.column1 &&
                this.column2 == blah.column2 &&
                this.column3 == blah.column3;
        }

        public override int GetHashCode()
        {
            return base.GetHashCode();
        }
    }
}

using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            
            // test
            HexRTBRow[] rows = new HexRTBRow[100];

            HexRTBRow test = new HexRTBRow("0058", "5C 00 41 00 70 00 70 00", "\\.A.p.p.");

            for (int i = 0; i < rows.Length; i++)
                rows[i] = test;

            hexRTBTest1.AddRows(rows);
        }
    }
}