public partial class FullTableRichTextBox : RichTextBox
    {
        public FullTableRichTextBox()
        {
            InitializeComponent();
        }
        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern IntPtr LoadLibrary(string libname);
        private static IntPtr RichEditModuleHandle;
        private const string RichEditDllV3 = "RichEd20.dll";
        private const string RichEditDllV41 = "Msftedit.dll";
        private const string RichEditClassV3A = "RichEdit20A";
        private const string RichEditClassV3W = "RichEdit20W";
        private const string RichEditClassV41W = "RICHEDIT50W";
        protected override CreateParams CreateParams
        {
            [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)]
            get
            {
                if (RichEditModuleHandle == IntPtr.Zero)
                {
                    RichEditModuleHandle = LoadLibrary(RichEditDllV41);
                    if (RichEditModuleHandle == IntPtr.Zero)
                    {
                        return base.CreateParams;
                    }
                }
                CreateParams theParams = base.CreateParams;
                theParams.ClassName = RichEditClassV41W;
                return theParams;
            }
        }

private void button6_Click(object sender, EventArgs e)
        {
            int p = 0;
            int k = Convert.ToInt32(nLenght.Value / Convert.ToInt32(nRows.Value));
            string position = "";
            switch (cb.SelectedIndex)
            {
                case 0: position = @"\trql"; break;
                case 1: position = @"\trqc"; break;
                case 2: position = @"\trqr"; break;
            }
            string strInsert = @"{\rtf1\ansi \trowd " + position + @"\par ";
            richTextBox1.SelectedRtf = strInsert;

            string Sh = Convert.ToInt32(nShrift.Value).ToString();
            for (int j = 1; j <= Convert.ToInt32(nRows.Value); j++)
            {
                p += k;
                if (j != Convert.ToInt32(nRows.Value)) strInsert += @"\cellx" + p.ToString();
                else { strInsert += @"\cellx" + p.ToString() + @"\pard\intbl \lang1033\f0\fs" + Sh + @" \r\n"; }
            }


            string cell = "";
            for (int i = 1; i <= Convert.ToInt32(nCells.Value); i++)
            {
                cell = "";
                for (int j = 1; j <= Convert.ToInt32(nRows.Value); j++) cell += @"\cell";
                if (i == 1) strInsert += @"\intbl" + cell + @"\row \r\n ";
                else strInsert += @"\intbl " + cell + @"\row \r\n ";
            }

            strInsert += @"\pard";
            richTextBox1.SelectedRtf = strInsert;
        }