How to Print Entire VB Form and Control the Printed Size

ID: Q84066

The information in this article applies to:

Microsoft Visual Basic Standard and Professional Editions for Windows, versions 2.0, 3.0
Microsoft Visual Basic programming system for Windows, version 1.0

SUMMARY

The Visual Basic for Windows PrintForm method provides a way to print the client area of a form. However, PrintForm does not allow you to control the size or proportion of the printed output, or to print the non-client area (the caption and border) of the form.

The following code example uses Windows API functions to print the entire form, and provides a method to control the size of the output. This method can also be used to print only the client area to a specific size and to control the position of the printed form to allow text or other graphics to be printed on the same page as the image of the form. The method is also applicable to printing all the forms in a project.

NOTE: This example will not work correctly on PostScript printers. For the example to work correctly, the printer must use a standard non-PostScript laser printer configuration (such as PCL/HP).

MORE INFORMATION

Combining the Windows API functions BitBlt, StretchBlt, CreateCompatibleDC, DeleteDC, SelectObject, and Escape allows greater control over the placement and size of the printed form than the PrintForm method. In a two-part process, the image of the entire form is captured by using BitBlt to make an invisible picture, and is turned into a persistent bitmap using the AutoRedraw property. Then the picture is printed using the method of printing a picture control (outlined in a separate article, found by querying for the following word in the Microsoft Knowledge Base):

CreateCompatibleDC

This method works on maximized forms as well as any smaller forms. The use of GetSystemMetrics allows a general procedure to handle different window border styles passed to it by querying the video driver for the size of windows standard borders in pixels.

The example below requires a single form with an invisible picture control.

Example

Add the following code to the general Declarations level of the form in a new project:

NOTE: All Declare statements below must be on one line each.

DefInt A-Z


Declare Function BitBlt Lib "gdi" (ByVal hDestDC, ByVal X, ByVal Y,
         ByVal nWidth, ByVal nHeight, ByVal hSrcDC, ByVal XSrc,
         ByVal YSrc, ByVal dwRop&)
Declare Function CreateCompatibleDC Lib "GDI" (ByVal hDC)
Declare Function SelectObject Lib "GDI" (ByVal hDC, ByVal hObject)
Declare Function StretchBlt Lib "GDI" (ByVal hDC, ByVal X, ByVal Y,
         ByVal nWidth, ByVal nHeight, ByVal hSrcDC, ByVal XSrc,
         ByVal YSrc, ByVal nSrcWidth, ByVal nSrcHeight, ByVal dwRop&amp;)
Declare Function DeleteDC Lib "GDI" (ByVal hDC)
Declare Function Escape Lib "GDI" (ByVal hDC, ByVal nEscape,
         ByVal nCount, lplnData As Any, lpOutData As Any)
Declare Function GetSystemMetrics Lib "User" (ByVal nIndex)

Const SM_CYCAPTION = 4
Const SM_CXBORDER = 5
Const SM_CYBORDER = 6
Const SM_CXDLGFRAME = 7
Const SM_CYDLGFRAME = 8
Const SM_CXFRAME = 32
Const SM_CYFRAME = 33

Const TWIPS = 1
Const PIXEL = 3
Const NILL = 0&
Const SRCCOPY = &HCC0020
Const NEWFRAME = 1

Dim ModeRatio, XOffset, YOffset As Integer

Set the following properties at design time:


   Control         Property      Setting
   -------         --------      -------
   Form1           Name          Form1 (default)
   Form1.Picture1  Name          Picture1 (default)
   Form1.Picture2  Name          Picture2 (default)
   Form1.File1     Name          File1 (default)
  
   (In Visual Basic version 1.0 for Windows, set the CtlName/FormName
    Property for the above objects instead of the Name property.)

You can add any other control(s) to the form to print. If a picture control is drawn at run time, be sure to set its AutoRedraw property to True so that the graphics will be transferred by the Windows API call BitBlt and eventually printed by StretchBlt.

Add the following code to the Form_Load procedure of Form1:


Sub Form_Load ()

' Size the form explicitly to match parameters of StretchBlt.
' Or use design time size to set coordinates.
        Form1.Move 1095, 1200, 8070, 5280

' Size two example controls.
        File1.Move 4080, 120, 2775, 2535
        Picture1.Move 240, 120, 2775, 2535

' Put up a caption to indicate how to print the form.
    Form1.Caption = "Double Click to Print Form And Text"

' The following *optional* code illustrates creating a persistent
' bitmap that will successfully StretchBlt to the printer.
    Picture1.AutoRedraw = -1  ' Create persistent bitmap of picture
                              ' contents.
    Picture1.Line (0, 0)-(Picture1.ScaleWidth / 2,
    Picture1.ScaleHeight / 2), , BF
    Picture1.AutoRedraw = 0   ' Toggle off.

' Make sure the temporary workspace picture is invisible.
    Picture2.visible = 0
End Sub

Add the following code to the general procedure level of the form:


Sub FormPrint (localname As Form)

' Display cross.
    screen.MousePointer = 2
' Calculate ratio between ScaleMode twips and ScaleMode pixel.
    localname.ScaleMode = PIXEL
    ModeRatio = localname.height \ localname.ScaleHeight
    localname.ScaleMode = TWIPS

XOffset = (localname.width - localname.ScaleWidth) \ ModeRatio
YOffset = (localname.height - localname.ScaleHeight) \ ModeRatio
CapSize% = GetSystemMetrics(SM_CYCAPTION) ' The height of the caption.

  ' The size of the fixed single border:
FudgeFactor% = GetSystemMetrics(SM_CYBORDER)
' The fudgefactor is due to inevitable mapping errors when converting
' logical pixels to screen pixels. This example is coded for 640X480
' screen resolution. For 800X600, remove the fudgefactor.
' For other resolutions, tweak for perfection!

Select Case localname.BorderStyle
Case 0      ' None.
        XOffset = 0
        YOffset = 0

Case 1      ' Fixed Single.
        XOffset = GetSystemMetrics(SM_CXBORDER)
        YOffset = GetSystemMetrics(SM_CYBORDER) + CapSize% - FudgeFactor%

Case 2      ' Sizeable.
        XOffset = GetSystemMetrics(SM_CXFRAME)
        YOffset = GetSystemMetrics(SM_CYFRAME) + CapSize% - FudgeFactor%

Case 3      ' Fixed Double.
        XOffset = GetSystemMetrics(SM_CXDLGFRAME) + FudgeFactor%
        YOffset = GetSystemMetrics(SM_CYDLGFRAME) + CapSize%

End Select

' Size the picture to the size of the form's non-client (complete)
' area.

   Picture2.Move 0, 0, localname.Width, localname.Height

' NOTE: Bitblt requires coordinates in pixels.
   Picture2.ScaleMode = PIXEL
' Clear Picture property of any previous BitBlt image.
   Picture2.Picture = LoadPicture("")
' -1 equals true: Must Have This!!!
   Picture2.AutoRedraw = -1
' Assign information of the destination bitmap.
   hDestDC% = Picture2.hDC
        X% = 0: Y% = 0
        nWidth% = Picture2.ScaleWidth
        nHeight% = Picture2.ScaleHeight

' Assign information of the source bitmap.
' Source is entire client area of form (plus non-client area)
' XOffset and YOffset settings depend on the BorderStyle chosen for
' the form.
        hSrcDC% = localname.hDC
        XSrc% = -XOffset: YSrc% = -YOffset
' Show transition to BitBlt by changing MousePointer.
   Screen.MousePointer = 4
' Assign the SRCCOPY constant to the Raster operation.
   dwRop& = SRCCOPY
   ' The following statement must appear on one line.
   Suc% = BitBlt(hDestDC%, X%, Y%, nWidth%, nHeight%, hSrcDC%, XSrc%,
                YSrc%, dwRop&)
' Start the StretchBlt process now.
' Assign persistent bitmap to Picture property:
   Picture2.Picture = Picture2.Image
' StretchBlt requires pixel coordinates.
       Picture2.ScaleMode = PIXEL
       Printer.ScaleMode = PIXEL
' * The following is an example of mixing text with StretchBlt.
       Printer.Print "This is a test of adding text and bitmaps "
       Printer.Print "This is a test of adding text and bitmaps "
       Printer.Print "This is a test of adding text and bitmaps "
' * If no text is printed in this procedure,
' * then you must add minimum: Printer.Print " "
' * to initialize Printer.hDC.

' Now display hour glass for the StretchBlt to printer.
   screen.MousePointer = 11

   hMemoryDC% = CreateCompatibleDC(Picture2.hDC)
   hOldBitMap% = SelectObject(hMemoryDC%, Picture2.Picture)

' You adjust the vertical stretch factor of the form in the
' argument "Printer.ScaleHeight - 1000":
   ApiError% = StretchBlt(Printer.hDC, 0, 192,
               Printer.ScaleWidth - 300, Printer.ScaleHeight - 1000,
               hMemoryDC%, 0, 0, Picture2.ScaleWidth,
               Picture2.ScaleHeight, SRCCOPY)  ' concatenate above
' The second parameter above allows for text already printed: modify
' accordingly.
   hOldBitMap% = SelectObject(hMemoryDC%, hOldBitMap%)
   ApiError% = DeleteDC(hMemoryDC%)
' * The following is an example of mixing text with StretchBlt.
' Set the printer currentY to allow for the size of the StretchBlt
' image. (This is relative to size of form and stretch factors chosen)
       Printer.currentY = 2392 ' In Twips.
       Printer.Print "This is for text after the StretchBlt"
       Printer.Print "This is for text after the StretchBlt"
       Printer.Print "This is for text after the StretchBlt"
   Printer.EndDoc
   ApiError% = Escape(Printer.hDC, NEWFRAME, 0, NILL, NILL)

' Reset MousePointer to default.
   Screen.MousePointer = 1

End Sub

Add the following code to the Double_Click event:


Sub Form_DblClick ()
   FormPrint Form1
End Sub

After saving the project, run the example.

Double-click the form to invoke the FormPrint procedure. Any form passed as a parameter to FormPrint will be printed. BitBlt will transfer the image to the Picture control, then StretchBlt transfers it to the printer DC, which will print the image that was transferred by BitBlt.

Optionally, you could place text or graphics in the picture (Form1.Picture2) before printing with StretchBlt or print directly to the page using Printer.Print or Printer.Line. If you choose the latter method, by adjusting the second and third parameters of StretchBlt, you can make the already printed content be followed by the image of the form on the same page.

REFERENCES

"Microsoft Windows Programmer's Reference Book and Online Resource" (Add-on kit number 1-55615-413-5)

Additional query words: 2.00 3.00


Keywords          : kbcode kbPrinting 
Version           : WINDOWS:1.0,2.0,3.0
Platform          : WINDOWS 
Issue type        :

Last Reviewed: May 14, 1999