Need to implemnt the RTF print in application

macupryk

Member
Joined
Apr 8, 2005
Messages
8
Programming Experience
10+
I am using the following class.
RichTextBoxPrint.vb

VB.NET:
Option Explicit On 
 
Imports System 
Imports System.Windows.Forms 
Imports System.Drawing 
Imports System.Runtime.InteropServices 
Imports System.Drawing.Printing 
 
Public Class RichTextBoxPrint 
Inherits RichTextBox 
' Convert the unit that is used by the .NET framework (1/100 inch) 
' and the unit that is used by Win32 API calls (twips 1/1440 inch) 
Private Const AnInch As Double = 14.4 
 
<StructLayout(LayoutKind.Sequential)> _ 
Private Structure RECT 
Public Left As Integer 
Public Top As Integer 
Public Right As Integer 
Public Bottom As Integer 
End Structure 
 
<StructLayout(LayoutKind.Sequential)> _ 
Private Structure CHARRANGE 
Public cpMin As Integer ' First character of range (0 for start of doc) 
Public cpMax As Integer ' Last character of range (-1 for end of doc) 
End Structure 
 
<StructLayout(LayoutKind.Sequential)> _ 
Private Structure FORMATRANGE 
Public hdc As IntPtr ' Actual DC to draw on 
Public hdcTarget As IntPtr ' Target DC for determining text formatting 
Public rc As RECT ' Region of the DC to draw to (in twips) 
Public rcPage As RECT ' Region of the whole DC (page size) (in twips) 
Public chrg As CHARRANGE ' Range of text to draw (see above declaration) 
End Structure 
 
Private Const WM_USER As Integer = &H400 
Private Const EM_FORMATRANGE As Integer = WM_USER + 57 
 
Private Declare Function SendMessage Lib "USER32" Alias "SendMessageA" (ByVal hWnd As IntPtr, ByVal msg As Integer, ByVal wp As IntPtr, ByVal lp As IntPtr) As IntPtr 
 
' Render the contents of the RichTextBox for printing 
' Return the last character printed + 1 (printing start from this point for next page) 
Public Shared Function Print(ByVal charFrom As Integer, ByVal charTo As Integer, ByVal e As PrintPageEventArgs) As Integer 
 
' Mark starting and ending character 
Dim cRange As CHARRANGE 
cRange.cpMin = charFrom 
cRange.cpMax = charTo 
 
' Calculate the area to render and print 
Dim rectToPrint As RECT 
rectToPrint.Top = e.MarginBounds.Top * AnInch 
rectToPrint.Bottom = e.MarginBounds.Bottom * AnInch 
rectToPrint.Left = e.MarginBounds.Left * AnInch 
rectToPrint.Right = e.MarginBounds.Right * AnInch 
 
' Calculate the size of the page 
Dim rectPage As RECT 
rectPage.Top = e.PageBounds.Top * AnInch 
rectPage.Bottom = e.PageBounds.Bottom * AnInch 
rectPage.Left = e.PageBounds.Left * AnInch 
rectPage.Right = e.PageBounds.Right * AnInch 
 
Dim hdc As IntPtr = e.Graphics.GetHdc() 
 
Dim fmtRange As FORMATRANGE 
fmtRange.chrg = cRange ' Indicate character from to character to 
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 whole size of page 
 
Dim res As IntPtr = IntPtr.Zero 
 
Dim wparam As IntPtr = IntPtr.Zero 
wparam = New IntPtr(1) 
 
' Move the pointer to the FORMATRANGE structure in memory 
Dim lparam As IntPtr = 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() 
End Function 
 
End Class
I need to be able to use this in a form

How do I go about declaring this?

I have a form called frmComments where I need to use this. How do I go about declaring this?

Me.txtComments = New RichTextBoxPrint ? This ok?

'
'txtComments
'
Me.txtComments.Location = New System.Drawing.Point(16, 64)
Me.txtComments.Name = "txtComments"
Me.txtComments.Size = New System.Drawing.Size(672, 344)
Me.txtComments.TabIndex = 7
Me.txtComments.Text = ""
This will be the size of the RichTextBox

Now so far I have the following error:
C:\Documents and Settings\mcupryk.MCUPRYK-1\My Documents\Visual Studio Projects\ZLAPS\LR_EXP\frmComments.vb(212): The variable 'txtComments' is either undeclared or was never assigned.



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

C:\Documents and Settings\mcupryk.MCUPRYK-1\My Documents\Visual Studio Projects\ZLAPS\LR_EXP\RichTextBoxPrint.vb(86):
Cannot refer to an instance member of a class from within a shared method or shared member initializer without an explicit instance of the class.
 
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