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The information in this article applies to:
- Professional Edition of Microsoft Visual Basic for Windows,
versions 1.0 (Professional Toolkit only), 2.0, and 3.0
SUMMARY
Visual Basic has only one native method for printing graphical objects, the
PrintForm method. The PrintForm method is limited to printing one form per
page and there is no way to control the placement of the image on the page
or to place text on the same page with the image.
This article shows by example how to print Windows metafiles, such as those
created by the graph control of the Professional edition, along with text,
to the printer, a form, or a picture control. The size and placement of
both the metafile and the text are under the program's control.
MORE INFORMATION
The following example shows you how to use Windows API functions to play a
metafile and draw text to the hDC of the chosen object. Choose from the
following objects: the printer object, a Visual Basic form, or a picture
control.
The example uses the graph control of the Professional Edition to create a
metafile for demonstration. Any Windows metafile, such as those provided in
the \VB\METAFILES directories, can be used as well. The technique allows
you to overlay text on the body of the metafile or overlay the metafile on
an area containing text -- by simply changing the order in which the
operations are executed. The last operation prints over the previous
operation.
NOTE: if the x and y scaling factors differ when metafiles are rendered,
the more restrictive of the two axes acts as the limiting factor.
Step-by-Step Example
Here are the steps necessary to construct a sample program that prints
metafiles and text:
- Start a new project in Visual Basic. Form1 is created by default.
- Add a Graph control (Graph1) and two Picture controls (Picture1
and Picture2) to the form.
- Build the menu. The following is an excerpt from the text format version
of the form. You can paste it into your form's text format file, or you
can build the menus by using the menu design dialog in Visual Basic.
Begin Menu mnuPrint
Caption = "&Print "
Begin Menu mnuToPic
Caption = "To P&icture"
End
Begin Menu mnuToForm
Caption = "To &Form"
End
Begin Menu mnuToPrinter
Caption = "To P&rinter"
End
End
- Add a code module (Module1) to the project by choosing New Module from
the File menu (ALT, F, M).
- Add the following code to the general declarations section of Module1:
Type RECT
left As Integer
top As Integer
right As Integer
bottom As Integer
End Type
Global lpDrawTextRect As RECT
Type Size
cx As Integer
cy As Integer
End Type
Global lpold_vpextent As Size
Global lpold_winextent As Size
Global lpoldsize As Size
Type POINTAPI
X As Integer
Y As Integer
End Type
Global lpoldwindoworg As POINTAPI
Global lpoldvieworg As POINTAPI
' Set actual location of the window on the device, in device units:
' Enter each of the following Declare statements on one, single line:
Declare Function PlayMetafile% Lib "GDI" (ByVal hDC%, ByVal hmf%)
Declare Function SetMapMode Lib "GDI" (ByVal hDC As Integer,
ByVal nMapMode As Integer) As Integer
Declare Function SetViewPortExt Lib "GDI" (ByVal hDC As Integer,
ByVal X As Integer, ByVal Y As Integer) As Long
Declare Function SetViewPortExtEx Lib "GDI" (ByVal hDC As Integer,
ByVal nX As Integer, ByVal nY As Integer, lpSize As Size) As Integer
Declare Function SetViewPortOrg Lib "GDI" (ByVal hDC As Integer,
ByVal X As Integer, ByVal Y As Integer) As Long
Declare Function SetViewPortOrgEx Lib "GDI" (ByVal hDC As Integer,
ByVal nX As Integer, ByVal nY As Integer, lpPoint As POINTAPI)
As Integer
Declare Function ScaleViewPortExtEx% Lib "GDI" (ByVal hDC%,
ByVal nXnum%, ByVal nXdenom%, ByVal nYnum%, ByVal nYdenom%,
lpSize As Size)
Declare Function GetViewportExtEx Lib "GDI" (ByVal hDC As Integer,
lpSize As Size) As Integer
Declare Function SetWindowExt Lib "GDI" (ByVal hDC As Integer,
ByVal X As Integer, ByVal Y As Integer) As Long
Declare Function SetWindowExtEx Lib "GDI" (ByVal hDC As Integer,
ByVal nX As Integer, ByVal nY As Integer, lpSize As Size) As Integer
Declare Function SetWindowOrg Lib "GDI" (ByVal hDC As Integer,
ByVal X As Integer, ByVal Y As Integer) As Long
Declare Function SetWindowOrgEx Lib "GDI" (ByVal hDC As Integer,
ByVal nX As Integer, ByVal nY As Integer, lpPoint As POINTAPI)
As Integer
Declare Function DrawText Lib "User" (ByVal hDC As Integer,
ByVal lpStr As String, ByVal nCount As Integer, lpRect As RECT,
ByVal wFormat As Integer) As Integer
Global Const DT_WORDBREAK = &H10
Global Const DT_CENTER = &H1
Global Const DT_RIGHT = &H2
Global Const DT_LEFT = &H0
Global Const MM_TEXT = 1
Global Const MM_ISOTROPIC = 7
- Add the following code to Module1:
' Enter the following four lines as one, single line:
Function PrintMetafile (printtarget As Integer, pmpicture As Control,
pmform As Form, mfsource As Control, originx As Integer,
originy As Integer, scalingx As Integer, scalingy As Integer)
As Integer
'*****************************************************************
'* PrintMetafileaccepts parameters and then prints either text or
'* Windows metafiles to one of three targets: printer, form or
'* picture control.
'*
'* Parameters:
'*
'* printtarget accepts three values:
'* 1 - sends output to printer object
'* 2 - sends output to picture control
'* 3 - sends output to form
'*
'* pmpicture - accepts a picture control for use as output target
'* pmform - accepts a form for use as the output target
'* mfsource - accepts a picture control containing the metafile
'* to be printed to the target
'*
'* originx, originy - specifies the x and y coordinates of the
'* origin of the output area
'*
'* scalingx, scalingy - specifies the scaling factors in percent
'* of the total output area, to create the
'* output window, controlling both x, y axes
'*
'********************************************************************
On Error GoTo handler
' Display hour glass:
screen.MousePointer = 11
' Get the x and y extents depending on the target of printmapping:
Select Case printtarget
Case 1 ' For printer target:
' Initialize the printer object's hDC from VB's perspective:
printer.Print " "
printer.ScaleMode = 3 ' pixels equivalent to MM_TEXT
pagewidth% = printer.ScaleWidth
pageheight% = printer.ScaleHeight
oldmapmode% = SetMapMode(printer.hDC, MM_ISOTROPIC)
' Make logical units equal to device units:
' The SDK recommends that this be done when using MM_ISOTROPIC:
success% = SetWindowOrgEx(printer.hDC, 0, 0, lpoldwindoworg)
' Enter each of the following statements as one, single line:
success% = SetWindowExtEx(printer.hDC, pagewidth%, pageheight%,
lpold_winextent)
success% = SetViewPortOrgEx(printer.hDC, originx, originy,
lpoldvieworg)
success% = SetViewPortExtEx(printer.hDC, pagewidth% / 100,
pageheight% / 100, lpold_vpextent)
success% = ScaleViewPortExtEx(printer.hDC, scalingx, 1,
scalingy, 1, lpoldsize)
' Send the metafile to the target hDC:
ApiError% = PlayMetafile(printer.hDC, mfsource.Picture)
If ApiError% = 0 Then
MsgBox "PlayMetaFile failed"
PrintMetafile = False
End If
' Reset device context to initial values:
' Enter each of the following statements as one, single line:
successl& = SetWindowOrg(printer.hDC, lpoldwindoworg.X,
lpoldwindoworg.Y)
successl& = SetWindowExt(printer.hDC, lpold_winextent.cx,
lpold_winextent.cy)
successl& = SetViewPortOrg(printer.hDC, lpoldvieworg.X,
lpoldvieworg.Y)
successl& = SetViewPortExt(printer.hDC, lpold_vpextent.cx,
lpold_vpextent.cy)
oldmapmode% = SetMapMode(printer.hDC, oldmapmode%)
PrintMetafile = True
Case 2 ' For picture1 target:
If TypeOf pmpicture Is PictureBox Then
pmpicture.ScaleMode = 3 ' pixels equivalent to MM_TEXT
pagewidth% = pmpicture.ScaleWidth
pageheight% = pmpicture.ScaleHeight
oldmapmode% = SetMapMode(pmpicture.hDC, MM_ISOTROPIC)
' Make logical units equal to device units:
' SDK recommends that this be done when using MM_ISOTROPIC:
' Enter each of following statements as one, single line:
success% = SetWindowOrgEx(pmpicture.hDC, 0, 0,
lpoldwindoworg)
success% = SetWindowExtEx(pmpicture.hDC, pagewidth%,
pageheight%, lpold_winextent)
success% = SetViewPortOrgEx(pmpicture.hDC, originx, originy,
lpoldvieworg)
success% = SetViewPortExtEx(pmpicture.hDC, pagewidth% / 100,
pageheight% / 100, lpold_vpextent)
success% = ScaleViewPortExtEx(pmpicture.hDC, scalingx, 1,
scalingy, 1, lpoldsize)
' Send the metafile to the target hDC:
ApiError% = PlayMetafile(pmpicture.hDC, mfsource.Picture)
If ApiError% = 0 Then
MsgBox "PlayMetaFile failed"
PrintMetafile = False
End If
' Reset device context to initial values:
' Enter each of following statements as one, single line:
successl& = SetWindowOrg(pmpicture.hDC, lpoldwindoworg.X,
lpoldwindoworg.Y)
successl& = SetWindowExt(pmpicture.hDC, lpold_winextent.cx,
lpold_winextent.cy)
successl& = SetViewPortOrg(pmpicture.hDC, lpoldvieworg.X,
lpoldvieworg.Y)
successl& = SetViewPortExt(pmpicture.hDC, lpold_vpextent.cx,
lpold_vpextent.cy)
oldmapmode% = SetMapMode(pmpicture.hDC, oldmapmode%)
PrintMetafile = True
Else
MsgBox "Target not a PictureBox control!"
screen.MousePointer = 0
PrintMetafile = False
Exit Function
End If
Case 3 ' For form target:
pmform.ScaleMode = 3
pagewidth% = pmform.ScaleWidth
pageheight% = pmform.ScaleHeight
oldmapmode% = SetMapMode(pmform.hDC, MM_ISOTROPIC)
' make logical units equal to device units
' The SDK recommends that this be done when using MM_ISOTROPIC:
success% = SetWindowOrgEx(pmform.hDC, 0, 0, lpoldwindoworg)
' Enter each of the following statements as one, single line:
success% = SetWindowExtEx(pmform.hDC, pagewidth%, pageheight%,
lpold_winextent)
success% = SetViewPortOrgEx(pmform.hDC, originx, originy,
lpoldvieworg)
success% = SetViewPortExtEx(pmform.hDC, pagewidth% / 100,
pageheight% / 100, lpold_vpextent)
success% = ScaleViewPortExtEx(pmform.hDC, scalingx, 1,
scalingy, 1, lpoldsize)
' Send the metafile to the target hDC:
ApiError% = PlayMetafile(pmform.hDC, mfsource.Picture)
If ApiError% = 0 Then
MsgBox "PlayMetaFile failed"
PrintMetafile = False
End If
' Reset device context to initial values:
' Enter each of the following statements as one, single line:
successl& = SetWindowOrg(pmform.hDC, lpoldwindoworg.X,
lpoldwindoworg.Y)
successl& = SetWindowExt(pmform.hDC, lpold_winextent.cx,
lpold_winextent.cy)
successl& = SetViewPortOrg(pmform.hDC, lpoldvieworg.X,
lpoldvieworg.Y)
successl& = SetViewPortExt(pmform.hDC, lpold_vpextent.cx,
lpold_vpextent.cy)
oldmapmode% = SetMapMode(pmform.hDC, oldmapmode%)
PrintMetafile = True
Case Else
' Enter the following statement as one, single line:
MsgBox "Unknown value passed to parameter printtarget
- exiting function"
screen.MousePointer = 0
Exit Function
End Select
screen.MousePointer = 0
Exit Function
handler:
' Enter the following statement as one, single line:
MsgBox "Function PrintMetafile has failed with error number " &
Trim(Str(Err)) & " - recheck your parameters"
screen.MousePointer = 0
PrintMetafile = False
Exit Function
End Function
' Enter the following four lines as one, single line:
Function PrintText (printtarget As Integer, pmpicture As Control,
pmform As Form, ptext As String, pfontname As String, pfontsize As
Integer, originx As Integer, originy As Integer, offsetx As Integer,
offsety As Integer, fuFormat)
'********************************************************************
'* PrintText accepts parameters and then prints text to the one of
'* three targets: printer, form or picture control.
'*
'* Parameters:
'* printtarget accepts three values:
'* 1 - sends output to printer object
'* 2 - sends output to picture control
'* 3 - sends output to form
'*
'* pmpicture - accepts picture control for use as output target
'* pmform - accepts form for use as the output target
'*
'* ptext - contains the string to be printed
'* pfontname - contains the fontname to be used
'* pfontsize - contains the fontsize to be used
'*
'* originx, originy - specifies the x and y coordinates of the
'* upper left origin of the output area
'*
'* offsetx, offsety - specifies the coordinates of the lower
'* right corner of the DrawText Rectangle
'* relative to the upper left corner
'*
'* fuFormat - Accepts four values for formatting the text
'* within the rectangle specified by the previous
'* four parameters
'* 0 - align left
'* 1 - align center
'* 2 - align right
'* 16 - do word wrapping in rectangle
'*
'* Return value is the height of the text in current logical units
'*
'********************************************************************
On Error GoTo handler2
' Display hour glass:
screen.MousePointer = 11
Select Case printtarget
Case 1
oldmapmode% = SetMapMode(printer.hDC, MM_TEXT)
printer.FontName = pfontname
printer.FontSize = pfontsize
lpDrawTextRect.left = originx
lpDrawTextRect.top = originy
lpDrawTextRect.right = originx + offsetx
lpDrawTextRect.bottom = originy + offsety
' Enter the following statement as one, single line:
success% = DrawText(printer.hDC, ptext, Len(ptext),
lpDrawTextRect, fuFormat)
PrintText = success%
' Reset device context to initial values:
oldmapmode% = SetMapMode(printer.hDC, oldmapmode%)
PrintText = success%
Case 2
If TypeOf pmpicture Is PictureBox Then
oldmapmode% = SetMapMode(pmpicture.hDC, MM_TEXT)
pmpicture.FontName = pfontname
pmpicture.FontSize = pfontsize
lpDrawTextRect.left = originx
lpDrawTextRect.top = originy
lpDrawTextRect.right = originx + offsetx
lpDrawTextRect.bottom = originy + offsety
' Enter the following statement as one, single line:
success% = DrawText(pmpicture.hDC, ptext, Len(ptext),
lpDrawTextRect, fuFormat)
PrintText = success%
' Reset device context to initial values:
oldmapmode% = SetMapMode(pmpicture.hDC, oldmapmode%)
Else
MsgBox "Target not a PictureBox control!"
screen.MousePointer = 0
PrintText = False
Exit Function
End If
Case 3
oldmapmode% = SetMapMode(pmform.hDC, MM_TEXT)
pmform.FontName = pfontname
pmform.FontSize = pfontsize
lpDrawTextRect.left = originx
lpDrawTextRect.top = originy
lpDrawTextRect.right = originx + offsetx
lpDrawTextRect.bottom = originy + offsety
' Enter the following statement as one, single line:
success% = DrawText(pmform.hDC, ptext, Len(ptext),
lpDrawTextRect, fuFormat)
PrintText = success%
' Reset device context to initial values:
oldmapmode% = SetMapMode(pmform.hDC, oldmapmode%)
PrintText = success%
Case Else
' Enter the following statement as one, single line:
MsgBox "Unknown value passed to parameter printtarget -
exiting function"
screen.MousePointer = 0
Exit Function
End Select
screen.MousePointer = 0
Exit Function
handler2:
' Enter the following statement as one, single line:
MsgBox "Function PrintText has failed with error number " &
Trim(Str(Err)) & " - recheck your parameters"
screen.MousePointer = 0
PrintText = False
Exit Function
End Function
- Add the following Sub procedures to the appropriate event procedure of
Form1:
Sub Form_Load ()
graph1.GraphStyle = 6
graph1.GraphType = 4 '3D Bar
graph1.NumSets = 3
graph1.Move 0, 0, 975, 855
picture2.Move 0, graph1.Top + graph1.Height, 975, 855
End Sub
Sub Form_Resize ()
picture1.Move Me.ScaleLeft, Me.ScaleHeight / 2, Me.ScaleWidth,
Me.ScaleHeight / 2
End Sub
Sub mnuToPic_Click ()
' Save the graph as a metafile to disk:
graph1.ImageFile = app.Path & "\GRAPHMF"
graph1.DrawMode = 6
graph1.Visible = False
' Allow time for graph to save the file to disk:
DoEvents
picture2.Picture = LoadPicture(app.Path & "\GRAPHMF.WMF")
' Or grab a metafile supplied with VB3:
' picture2.Picture =
LoadPicture("C:\VB\METAFILE\BUSINESS\CENT.WMF")
' Allow the file to be loaded:
DoEvents
ret% = PrintMetafile(2, picture1, Me, picture2, 0, 0, 100, 100)
NL$ = Chr$(13) & Chr$(10)
' Enter each of the following statements as one, single line:
st1$ = "This is a string of characters that will be wrapped to fit
the rectangle!"
st2$ = "This is one string!" & NL$ & "This on the second line" & NL$
& "and this is on the third!"
fn$ = "Courier New"
ret% = PrintMetafile(2, picture1, Me, picture2, 62, 170, 25, 25)
ret% = PrintMetafile(2, picture1, Me, picture2, 62, 200, 16, 16)
' Word wrap in the rectangle:
' Enter the following statement as one, single line:
ret% = PrintText(2, picture1, Me, st1$, fn$, 13, 190, 100,
139, 139, 16)
' Center the text in the rectangle:
ret% = PrintText(2, picture1, Me, st2$, fn$, 13, 69, 47, 254, 139, 1)
End Sub
Sub mnuToForm_Click ()
' Save the graph as a metafile to disk:
graph1.ImageFile = app.Path & "\GRAPHMF"
graph1.DrawMode = 6
graph1.Visible = False
' Allow time for graph to save the file to disk:
DoEvents
picture2.Picture = LoadPicture(app.Path & "\GRAPHMF.WMF")
' or grab a metafile supplied with VB3:
' picture2.Picture =
LoadPicture("C:\VB\METAFILE\BUSINESS\CENT.WMF")
' Allow the file to be loaded:
DoEvents
ret% = PrintMetafile(3, picture1, Me, picture2, 0, 0, 100, 100)
NL$ = Chr$(13) & Chr$(10)
' Enter each of the following statements as one, single line:
st1$ = "This is a string of characters that will be wrapped to fit
the rectangle!"
st2$ = "This is one string!" & NL$ & "This on the second line" &
NL$ & "and this is on the third!"
fn$ = "Times New Roman"
ret% = PrintMetafile(3, picture1, Me, picture2, 62, 170, 25, 25)
ret% = PrintMetafile(3, picture1, Me, picture2, 62, 200, 16, 16)
' Word wrap in the rectangle:
' Enter the following statement as one, single line:
ret% = PrintText(3, picture1, Me, st1$, fn$, 13, 190, 100,
139, 139, 16)
' Center the text in the rectangle:
ret% = PrintText(3, picture1, Me, st2$, fn$, 13, 69, 47, 254, 139, 1)
End Sub
Sub mnuToPrinter_Click ()
' Save the graph as a metafile to disk:
graph1.ImageFile = app.Path & "\GRAPHMF"
graph1.DrawMode = 6
graph1.Visible = False
' Allow time for graph to save the file to disk:
DoEvents
picture2.Picture = LoadPicture(app.Path & "\GRAPHMF.WMF")
' or grab a metafile supplied with VB3
' picture1.Picture =
LoadPicture("C:\VB\METAFILE\BUSINESS\CENT.WMF")
' Allow the file to be loaded:
DoEvents
ret% = PrintMetafile(1, picture1, Me, picture2, 0, 0, 100, 100)
NL$ = Chr$(13) & Chr$(10)
' Enter each of the following statements as one, single line:
st1$ = "This is a string of characters that will be wrapped to fit
the rectangle!"
st2$ = "This is one string!" & NL$ & "This on the second line" & NL$
& "and this is on the third!"
fn$ = "Times New Roman"
ret% = PrintMetafile(1, picture1, Me, picture2, 540, 1100, 29, 29)
ret% = PrintMetafile(1, picture1, Me, picture2, 540, 1300, 19, 19)
' Word wrap in the rectangle:
' Enter the following statement as one, single line:
ret% = PrintText(1, picture1, Me, st1$, fn$, 13, 1100, 300,
400, 300, 16)
' Center the text in the rectangle:
' Enter the following statement as one, single line:
ret% = PrintText(1, picture1, Me, st2$, fn$, 13, 1040, 690, 600,
139, 1)
printer.EndDoc
End Sub
- Save the project and run the program by pressing the F5 key.
- Select any of the three targets for the composite of text and
metafiles to be rendered.
- The code in the three menu events (mnuToPrinter_Click, mnuToForm_Click,
and mnuToPic_Click) are just three parallel examples demonstrating the
technique. The PrintMetafile and PrintText functions are designed to
be generic wrappers for the API functions used.
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