private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            var directory = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetEntryAssembly().Location);
            var file = System.IO.Path.Combine(directory, "contractText.rtf");
            _rtb.LoadFile(file);
            _rtb.SelectionBullet = true;
            var bullet = _rtb.BulletIndent;
            ReplaceAll(_rtb,"idContract", IdContractglob.ToString());
            ReplaceAll(_rtb,"date", dateFrom);
            ReplaceAll(_rtb,"FIOSOB", tbFIOSOB.Text);
            ReplaceAll(_rtb,"SerNomPassportSOB", tbSerNomPassportSOB.Text);
            ReplaceAll(_rtb,"KemVadanDataSOB", tbKemVadanDataSOB.Text);
         
            _rtb.SaveFile("g:\\a.rtf");

            PrintDialog printDialog = new PrintDialog();
            PrintDocument documentToPrint = new PrintDocument();
            documentToPrint.BeginPrint += new System.Drawing.Printing.PrintEventHandler(BeginPrint);
            documentToPrint.PrintPage += new System.Drawing.Printing.PrintPageEventHandler(PrintPage);
            documentToPrint.DocumentName = "Договор №" + IdContractglob + " от " + dateFrom;
            if (printDialog.ShowDialog() == true)
            {
                documentToPrint.Print();
            }
        }
        private void BeginPrint(object sender, System.Drawing.Printing.PrintEventArgs e)
		{
			_checkPrint = 0;
		}
        
        private void PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
		{
			// Print the content of RichTextBox. Store the last character printed.
			_checkPrint = _rtb.Print(_checkPrint, _rtb.TextLength, e);

			// Check for more pages
			if (_checkPrint < _rtb.TextLength)
				e.HasMorePages = true;
			else
				e.HasMorePages = false;
		}
        public void ReplaceAll(System.Windows.Forms.RichTextBox myRtb, string word, string replacement)
        {
            int i = 0;
            int n = 0;
            int a = replacement.Length - word.Length;
            foreach (Match m in Regex.Matches(myRtb.Text, word))
            {
                myRtb.Select(m.Index + i, word.Length);
                i += a;
                myRtb.SelectedText = replacement;
                n++;
            }
        }

        private void DocumentToPrint_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
        {
            StringReader reader = new StringReader(_rtb.Text);
            float LinesPerPage = 0;
            float YPosition = 0;
            int Count = 0;
            float LeftMargin = e.MarginBounds.Left;
            float TopMargin = e.MarginBounds.Top;
            string Line = null;
            Font PrintFont = this._rtb.Font;
            SolidBrush PrintBrush = new SolidBrush(System.Drawing.Color.Black);

            LinesPerPage = e.MarginBounds.Height / PrintFont.GetHeight(e.Graphics);

            while (Count < LinesPerPage && ((Line = reader.ReadLine()) != null))
            {
                YPosition = TopMargin + (Count * PrintFont.GetHeight(e.Graphics));
                e.Graphics.DrawString(Line, PrintFont, PrintBrush, LeftMargin, YPosition, new StringFormat());
                Count++;
            }

            if (Line != null)
            {
                e.HasMorePages = true;
            }
            else
            {
                e.HasMorePages = false;
            }
            PrintBrush.Dispose();
        }

 class RichTextBoxPrintCtrl : RichTextBox
    {//Convert the unit used by the .NET framework (1/100 inch) 
        //and the unit used by Win32 API calls (twips 1/1440 inch)
        private const double anInch = 14.4;

        [StructLayout(LayoutKind.Sequential)]
        private struct RECT
        {
            public int Left;
            public int Top;
            public int Right;
            public int Bottom;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct CHARRANGE
        {
            public int cpMin;         //First character of range (0 for start of doc)
            public int cpMax;           //Last character of range (-1 for end of doc)
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct FORMATRANGE
        {
            public IntPtr hdc;             //Actual DC to draw on
            public IntPtr hdcTarget;       //Target DC for determining text formatting
            public RECT rc;                //Region of the DC to draw to (in twips)
            public RECT rcPage;            //Region of the whole DC (page size) (in twips)
            public CHARRANGE chrg;         //Range of text to draw (see earlier declaration)
        }

        private const int WM_USER = 0x0400;
        private const int EM_FORMATRANGE = WM_USER + 57;

        [DllImport("USER32.dll")]
        private static extern IntPtr SendMessage(IntPtr hWnd, int msg, IntPtr wp, IntPtr lp);

        // Render the contents of the RichTextBox for printing
        //	Return the last character printed + 1 (printing start from this point for next page)
        public int Print(int charFrom, int charTo, PrintPageEventArgs e)
        {
            //Calculate the area to render and print
            RECT rectToPrint;
            rectToPrint.Top = (int)(e.MarginBounds.Top * anInch);
            rectToPrint.Bottom = (int)(e.MarginBounds.Bottom * anInch);
            rectToPrint.Left = (int)(e.MarginBounds.Left * anInch);
            rectToPrint.Right = (int)(e.MarginBounds.Right * anInch);

            //Calculate the size of the page
            RECT rectPage;
            rectPage.Top = (int)(e.PageBounds.Top * anInch);
            rectPage.Bottom = (int)(e.PageBounds.Bottom * anInch);
            rectPage.Left = (int)(e.PageBounds.Left * anInch);
            rectPage.Right = (int)(e.PageBounds.Right * anInch);

            IntPtr hdc = e.Graphics.GetHdc();

            FORMATRANGE fmtRange;
            fmtRange.chrg.cpMax = charTo;				//Indicate character from to character to 
            fmtRange.chrg.cpMin = charFrom;
            fmtRange.hdc = hdc;                    //Use the same DC for measuring and rendering
            fmtRange.hdcTarget = hdc;              //Point at printer hDC
            fmtRange.rc = rectToPrint;             //Indicate the area on page to print
            fmtRange.rcPage = rectPage;            //Indicate size of page

            IntPtr res = IntPtr.Zero;

            IntPtr wparam = IntPtr.Zero;
            wparam = new IntPtr(1);

            //Get the pointer to the FORMATRANGE structure in memory
            IntPtr lparam = IntPtr.Zero;
            lparam = Marshal.AllocCoTaskMem(Marshal.SizeOf(fmtRange));
            Marshal.StructureToPtr(fmtRange, lparam, false);

            //Send the rendered data for printing 
            res = SendMessage(Handle, EM_FORMATRANGE, wparam, lparam);

            //Free the block of memory allocated
            Marshal.FreeCoTaskMem(lparam);

            //Release the device context handle obtained by a previous call
            e.Graphics.ReleaseHdc(hdc);

            //Return last + 1 character printer
            return res.ToInt32();
        }

    }