create bold,Italic Paragraph Tag...in Richtextbox

[bettiahamit]

here i created sequence no. with every paragraph line

..

like...

<p local_id = P-100>aaaaaaaaaaa aaaaaaaaaaaaaa< \p>
<p local_id = P-101>bbbbbbbbbbb bbbbbbbbbbbbbb< \p>
<p local_id = P-102>vvvvvvvvvvv vvvvv<\p>



and show in richtextbox control..

here is my code:-

private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                OpenFileDialog ofd = new OpenFileDialog();
                //Font fonttext = null;
 
                ofd.DefaultExt = "*rtf";
                ofd.Filter = "RTF File|*.rtf";
                ofd.ShowDialog();
                textBox1.Text = ofd.FileName.ToString();
                filepath = ofd.FileName.ToString();
 
                //FileStream fs = new FileStream(filepath, FileMode.Open, FileAccess.Read);
                //StreamReader sr = new StreamReader(fs);
 
                richTextBox1.LoadFile(filepath,RichTextBoxStreamType.RichText);
                string inputstring = richTextBox1.Text;
                StringBuilder sb = new StringBuilder(inputstring);
                //Font fonttext = new Font(sb);
 
                //if (fonttext.Bold)
                //sb.Append(@"<B>");
 
                //string xx = inputstring;
                //string yy = xx.Replace("", "");
                ////if (fonttext.Bold)
                ////    sb.Insert(0, "<B>");
                ////else if
                ////    (fonttext.Italic)
                ////    sb.Insert(0, "<I>");
                ////else
 
                sb.Insert(0, "<p>");
                //string yy = xx.Replace("", "");
                //sb.Replace("<p>", "");
                //int num = 0;
                // sb.Replace("<p>"
 
                sb.Replace("\n", "</p>" + "\n" + "<p>");
                sb.Replace("<p>" + "</p>", "");
                sb.Append("</p>");
                sb.Replace("<p>" + "</p>", "");
                sb.Replace("\n\n", "\n");
                sb.Replace("\n\n", "\n");
                sb.Replace("\n\n", "\n");
                sb.Replace("\n\n", "\n");
                sb.Replace("\n\n", "\n");
                sb.Replace("\n\n", "\n");
                int p=0;
                string xx = sb.ToString ();
                int ppara = 0;
                ppara = xx.IndexOf("<p>", 0);
                while (ppara!=  -1)
                {
                    p = p+1;
                    ////string f1 = Convert.ToString(p);
                    //f1.ToString().PadLeft(8);
                    xx = xx.Remove(ppara, 3);
                    //if (fonttext.Bold)
                    //    xx = xx.Insert(ppara, "<p local-id=\"B-" + p + "\">");
                    //else
                        xx = xx.Insert(ppara, "<p local-id=\"p-" + p + "\">");
                    ppara = xx.IndexOf("<p>", ppara+3);
                }
 
                richTextBox1.Text = xx.ToString();
 
            }
           //}
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

problem is that, if there is any bold,italic paragraph.then he show output in richtextbox like...
<p local-id=\"p-" + p + "\">">wwwwwwwww wwwww<\p>
<B local-id=\"B-" + p + "\">">aaaaaaaaa aaaa<\B>
<I local-id=\"I-" + p + "\">">yyyyyyyyy yyyyy<\I>

then how??