Print with RichTextBox

Hello,

1.

Create a class RichTextBoxPrintCtrl that inherits from RichTextBox.
2.

Use the RichTextBoxPrintCtrl class in your upgraded project.

To create a class that inherits from the RichTextBox class

1.

Use Visual Basic 2005 to create a new Class Library project named RichTextBoxPrintCtrl.

By default, Class1.vb is created.
2.

Rename the Class1.vb file to RichTextBoxPrintCtrl.vb.
3.

In Solution Explorer, right-click on References, and then click on Add Reference.
4.

In the Add Reference dialog, double-click on System.Drawing.dll, then on System.Windows.Forms.dll.
5.

To add the references, click OK.
6.

Delete the existing code in RichTextBoxPrintCtrl.vb.
7.

Add the following code to RichTextBoxPrintCtrl.vb :

Option Explicit On

Imports System
Imports System.Windows.Forms
Imports System.Drawing
Imports System.Runtime.InteropServices
Imports System.Drawing.Printing

Namespace RichTextBoxPrintCtrl
Public Class RichTextBoxPrintCtrl
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

Private WithEvents m_PrintDocument As Printing.PrintDocument
Private intCharactersToPrint As Integer
Private intCurrentPosition As Integer

<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
' First character of range (0 for start of doc)
Public cpMin As Integer
' Last character of range (-1 for end of doc)
Public cpMax As Integer
End Structure

<StructLayout(LayoutKind.Sequential)> _
Private Structure FORMATRANGE
' Actual DC to draw on
Public hdc As IntPtr
' Target DC for determining text formatting
Public hdcTarget As IntPtr
' Region of the DC to draw to (in twips)
Public rc As Rect
' Region of the whole DC (page size) (in twips)
Public rcPage As Rect
' Range of text to draw (see above declaration)
Public chrg As CHARRANGE
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

Public Sub SelPrint()

'print only the selected text if any is selected
If Me.SelectionLength > 0 Then
intCharactersToPrint = Me.SelectionStart + Me.SelectionLength
intCurrentPosition = Me.SelectionStart
Else
'otherwise print the entire document
intCharactersToPrint = Me.TextLength
intCurrentPosition = 0
End If

m_PrintDocument.Print()

End Sub
' Render the contents of the RichTextBox for printing
' Return the last character printed + 1 (printing starts from
' this point for the next page)
Private 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
' Indicate character from to character to
fmtRange.chrg = cRange
' Use the same DC for measuring and rendering
fmtRange.hdc = hdc
' Point at printer hDC
fmtRange.hdcTarget = hdc
' Indicate the area on page to print
fmtRange.rc = rectToPrint
' Indicate whole size of page
fmtRange.rcPage = rectPage

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 the last + 1 character printed
Return res.ToInt32

End Function
Public ReadOnly Property PrintDocument() As Printing.PrintDocument
Get
If m_PrintDocument Is Nothing Then
m_PrintDocument = New Printing.PrintDocument
End If

Return m_PrintDocument
End Get
End Property

Private Sub m_PrintDocument_PrintPage(ByVal sender As _
Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) _
Handles m_PrintDocument.PrintPage
' Print the content of the RichTextBox.
' Store the last character printed.

intCurrentPosition = Me.Print(intCurrentPosition, _
intCharactersToPrint, e)

' Look for more pages by checking
If intCurrentPosition < intCharactersToPrint Then
e.HasMorePages = True
Else
e.HasMorePages = False
End If

End Sub
End Class
End Namespace

8.

To create RichTextBoxPrintCtrl.dll, click on Build Solution in the Build menu.

To use the RichTextBoxPrintCtrl class in your upgraded project

1.

Open your upgraded Windows application project in Visual Basic 2005.
2.

From the toolbox, drag a PrintDialog component onto the form containing the RichTextBox control.
3.

In the Tools menu, click on Customize Toolbox.
4.

Click on .NET Framework Components, browse for RichTextBoxPrintCtrl.dll, and then click OK.
5.

From the toolbox, drag a RichTextBoxPrintCtrl control onto the form.
6.

Set the properties of RichTextBoxPrintCtrl to match those of your original RichTextBox control.
7.

Remove the RichTextBox control, then rename the RichTextBoxPrintCtrl control to match the name of your original RichTextBox control.
8.

Double-click on the form to open the code editor.
9.

Add the following code to the Button_Click event handler (or wherever you called SelPrint in the original code):

' NOTE: Replace "Button1" with the name of your actual Print button
Private Sub Button1_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button1.Click

'associate the correct printdocument to the printdialog
PrintDialog1.Document = Me.RichTextBoxPrintCtrl1.PrintDocument

If PrintDialog1.ShowDialog() = DialogResult.OK Then
Me.RichTextBoxPrintCtrl1.SelPrint()
End If
End Sub

Thank you, but I'm getting a printer violation error directly

I already have this effective DLL in another one of my projects and it's the same problem

Thank you for your help, but I will have to check all my programs that use a printer and see what the problem is, and thank you again