SelPrint property was not upgraded
In Visual Basic 6.0, the SelPrint method of a RichTextBox control could be used to print the contents of the control. It took a single argument, hDC, which specified the device context of the device.
In Visual Basic 2008, the SelPrint method no longer exists and device contexts are no longer used for printing. The RichTextBox control does not provide a method to print its content. However, you can extend the RichTextBox class to use the EM_FORMATRANGE message. You can then send the content of a RichTextBox to an output device, such as a printer. The two steps to accomplishing this process are:
Create a RichTextBoxPrintCtrl class that inherits from RichTextBox.
Use the RichTextBoxPrintCtrl class in your upgraded project.
To create a class that inherits from the RichTextBox class
Use Visual Basic 2008 to create a new Class Library project named RichTextBoxPrintCtrl.
By default, Class1.vb is created.
Change the name of the Class1.vb file to RichTextBoxPrintCtrl.vb.
In Solution Explorer, right-click References, and then click Add Reference.
In the Add Reference dialog box, double-click System.Drawing.dll, and then double-click System.Windows.Forms.dll.
To add the references, click OK.
Delete the existing code in RichTextBoxPrintCtrl.vb.
Copy 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 start from ' this point for 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 NamespaceTo create RichTextBoxPrintCtrl.dll, click Build Solution on the Build menu.
To use the RichTextBoxPrintCtrl class in your upgraded project
Open your upgraded Windows Application project in Visual Basic 2008.
From the Toolbox, drag a PrintDialog component to the form that contains the RichTextBox control.
On the Tools menu, click Customize Toolbox.
Click .NET Framework Components, click Browse, click to select RichTextBoxPrintCtrl.dll, and then click OK.
From the Toolbox, drag a RichTextBoxPrintCtrl onto the form.
Set the properties of the RichTextBoxPrintCtrl to match the properties of your original RichTextBox control.
Delete the RichTextBox control, and then rename the RichTextBoxPrintCtrl control to the name of your original RichTextBox control.
Double-click the form to open the code editor.
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