:rolleyes: I have a control that I drag and drop.

I would like to use the below instead of building a dll.
I want to call the subroutine. Is there a way I can do so?
I am not aloud to use build any extra dlls in the project.
If so can you please provide me the steps to call the subroutine and what needs to
be modified in the below.

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

<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 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
End Namespace