'SUMMARY 'This article shows how to capture any form or window including the screen into a Visual Basic Picture object. Once the on-screen image is captured in the Picture object, it can easily be printed using the PaintPicture method of the Visual Basic Printer object. ' ' 'MORE Information 'The included example provides several useful routines for capturing images. All of the routines have been written to work under both 16- and 32-bit Windows platforms and they contain full palette support. The routines in the example can: 'Capture the entire contents of a form. 'Capture the client area of a form. 'Capture the entire screen. 'Capture the active window on the screen. 'Capture any portion of any window given a handle to it. 'Create a Picture object from a bitmap and a palette. 'Print a Picture object as large as possible on the page. 'Visual Basic 4.0 introduced a new Picture object. The Picture object is actually a standard OLE type and it is documented in the Control Developer's Kit (CDK.) 'The CDK includes the function OleCreatePictureIndirect that you can use to construct new Picture objects from Visual Basic 4.0. The routine CreateBitmapPicture in the example calls OleCreatePictureIndirect to build a Picture object from a handle to a bitmap and a handle to a palette. If the Picture includes a valid palette, Visual Basic will know to use it when rendering the Picture to the screen or printer. The CreateBitmapPicture routine is used by the CaptureWindow routine to construct Picture objects containing a bitmap of a part or all of a window. 'The CaptureWindow routine in the example captures any portion of a window given a window handle. The routine includes several parameters for describing the exact portion of the window to capture. Capture Window works by copying the on-screen image of a window into a new bitmap. It also checks to see if the screen has a palette and if so it makes a copy of it. CaptureWindow then calls CreateBitmapPicture to construct a bitmap from the newly created bitmap and palette. 'The CaptureForm, CaptureClient, CaptureScreen, and CaptureActiveWindow routines included in the example all use CaptureWindow to capture specific windows. CaptureForm and CaptureClient both call Capture window and pass it the hWnd property of a Form object. CaptureScreen simply gets the handle to the desk top window and calls CaptureWindow. Similarly, CaptureActiveWindow just gets the window handle of the active window and calls CaptureWindow. 'Once the desired image is captured in a Picture object, it is easy to print in Visual Basic 4.0 using the PaintPicture method of the Printer object. The example provides the routine PrintPictureToFitPage that uses the PaintPictureMethod to print the captured images as large as possible in the printable area of the page. ' 'example 'Start a new project. Form1 is created by default. 'Place six CommandButtons on the form along the left side. 'Place one picture box on the form to the right of the buttons. 'Put the following code in Form1:'-------------------------------------------------------------------- ' Capture the entire screen. Private Sub Command1_Click() Set Picture1.Picture = CaptureScreen() End Sub' Capture the entire form including title and border. Private Sub Command2_Click() Set Picture1.Picture = CaptureForm(Me) End Sub' Capture the client area of the form. Private Sub Command3_Click() Set Picture1.Picture = CaptureClient(Me) End Sub ' Capture the active window after two seconds. Private Sub Command4_Click() MsgBox "Two seconds after you close this dialog " & "the active window will be captured." ' Wait for two seconds. Dim EndTime As Date EndTime = DateAdd("s", 2, Now) Do Until Now > EndTime DoEvents Loop ' Set focus back to form. Me.SetFocus End Sub' Print the current contents of the picture box. Private Sub Command5_Click() PrintPictureToFitPage Printer, Picture1.Picture Printer.EndDoc End Sub Private Sub Command6_Click() Set Picture1.Picture = Nothing End Sub ' Initialize the form and controls. Private Sub Form_Load() Me.Caption = "Capture and Print Example" Command1.Caption = "&Screen" Command2.Caption = "&Form" Command3.Caption = "&Client" Command4.Caption = "&Active" Command5.Caption = "&Print" Command6.Caption = "C&lear" Picture1.AutoSize = True End Sub
Add a new standard module to the project (module1 by default). Put the following code in the new module: '-------------------------------------------------------------------- ' Visual Basic 4.0 16/32 Capture Routines ' This module contains several routines for capturing windows into a ' picture. All the routines work on both 16 and 32 bit Windows ' platforms. ' The routines also have palette support. ' CreateBitmapPicture - Creates a picture object from a bitmap and ' palette. ' CaptureWindow - Captures any window given a window handle. ' CaptureActiveWindow - Captures the active window on the desktop. ' CaptureForm - Captures the entire form. ' CaptureClient - Captures the client area of a form. ' CaptureScreen - Captures the entire screen. ' PrintPictureToFitPage - prints any picture as big as possible on ' the page. ' NOTES ' - No error trapping is included in these routines.'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Option Explicit Option Base 0 Private Type PALETTEENTRY peRed As Byte peGreen As Byte peBlue As Byte peFlags As Byte End TypePrivate Type LOGPALETTE palVersion As Integer palNumEntries As Integer palPalEntry(255) As PALETTEENTRY ' Enough for 256 colors. End TypePrivate Type GUID Data1 As Long Data2 As Integer Data3 As Integer Data4(7) As Byte End Type Private Const RASTERCAPS As Long = 38 Private Const RC_PALETTE As Long = &H100 Private Const SIZEPALETTE As Long = 104
Private Type RECT Left As Long Top As Long Right As Long Bottom As Long End Type Private Declare Function CreateCompatibleDC Lib "GDI32" (ByVal hDC As Long) As Long Private Declare Function CreateCompatibleBitmap Lib "GDI32" (ByVal hDC As Long, ByVal nWidth As Long, ByVal nHeight As Long) As Long Private Declare Function GetDeviceCaps Lib "GDI32" (ByVal hDC As Long, ByVal iCapabilitiy As Long) As Long Private Declare Function GetSystemPaletteEntries Lib "GDI32" (ByVal hDC As Long, ByVal wStartIndex As Long, ByVal wNumEntries As Long, lpPaletteEntries As PALETTEENTRY) As Long Private Declare Function CreatePalette Lib "GDI32" (lpLogPalette As LOGPALETTE) As Long Private Declare Function SelectObject Lib "GDI32" (ByVal hDC As Long, ByVal hObject As Long) As Long Private Declare Function BitBlt Lib "GDI32" (ByVal hDCDest As Long, ByVal XDest As Long, ByVal YDest As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hDCSrc As Long, ByVal XSrc As Long, ByVal YSrc As Long, ByVal dwRop As Long) As Long Private Declare Function DeleteDC Lib "GDI32" (ByVal hDC As Long) As Long Private Declare Function GetForegroundWindow Lib "USER32" () As Long Private Declare Function SelectPalette Lib "GDI32" (ByVal hDC As Long, ByVal hPalette As Long, ByVal bForceBackground As Long) As Long Private Declare Function RealizePalette Lib "GDI32" (ByVal hDC As Long) As Long Private Declare Function GetWindowDC Lib "USER32" (ByVal hWnd As Long) As Long Private Declare Function GetDC Lib "USER32" (ByVal hWnd As Long) As Long Private Declare Function GetWindowRect Lib "USER32" (ByVal hWnd As Long, lpRect As RECT) As Long Private Declare Function ReleaseDC Lib "USER32" (ByVal hWnd As Long, ByVal hDC As Long) As Long Private Declare Function GetDesktopWindow Lib "USER32" () As Long Private Type PicBmp Size As Long Type As Long hBmp As Long hPal As Long Reserved As Long End Type Private Declare Function OleCreatePictureIndirect Lib "olepro32.dll" (PicDesc As PicBmp, RefIID As GUID, ByVal fPictureOwnsHandle As Long, IPic As IPicture) As Long''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' CreateBitmapPicture ' - Creates a bitmap type Picture object from a bitmap and ' palette. ' hBmp ' - Handle to a bitmap. ' hPal ' - Handle to a Palette. ' - Can be null if the bitmap doesn't use a palette. ' Returns ' - Returns a Picture object containing the bitmap.''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' Public Function CreateBitmapPicture(ByVal hBmp As Long, ByVal hPal As Long) As Picture Dim r As Long Dim Pic As PicBmp ' IPicture requires a reference to "Standard OLE Types." Dim IPic As IPicture Dim IID_IDispatch As GUID ' Fill in with IDispatch Interface ID. With IID_IDispatch .Data1 = &H20400 .Data4(0) = &HC0 .Data4(7) = &H46 End With ' Fill Pic with necessary parts. With Pic .Size = Len(Pic) ' Length of structure. .Type = vbPicTypeBitmap ' Type of Picture (bitmap). .hBmp = hBmp ' Handle to bitmap. .hPal = hPal ' Handle to palette (may be null). End With ' Create Picture object. r = OleCreatePictureIndirect(Pic, IID_IDispatch, 1, IPic) ' Return the new Picture object. Set CreateBitmapPicture = IPic End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' CaptureWindow ' - Captures any portion of a window. ' ' hWndSrc ' - Handle to the window to be captured. ' Client ' - If True CaptureWindow captures from the client area of the ' window. ' - If False CaptureWindow captures from the entire window. ' LeftSrc, TopSrc, WidthSrc, HeightSrc ' - Specify the portion of the window to capture. ' - Dimensions need to be specified in pixels. ' Returns ' - Returns a Picture object containing a bitmap of the specified ' portion of the window that was captured. ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' Public Function CaptureWindow(ByVal hWndSrc As Long, ByVal Client As Boolean, ByVal LeftSrc As Long, ByVal TopSrc As Long, ByVal WidthSrc As Long, ByVal HeightSrc As Long) As Picture Dim hDCMemory As Long Dim hBmp As Long Dim hBmpPrev As Long Dim r As Long Dim hDCSrc As Long Dim hPal As Long Dim hPalPrev As Long Dim RasterCapsScrn As Long Dim HasPaletteScrn As Long Dim PaletteSizeScrn As Long Dim LogPal As LOGPALETTE ' Depending on the value of Client get the proper device context. If Client Then hDCSrc = GetDC(hWndSrc) ' Get device context for client area. Else hDCSrc = GetWindowDC(hWndSrc) ' Get device context for entire window. End If ' Create a memory device context for the copy process. hDCMemory = CreateCompatibleDC(hDCSrc) ' Create a bitmap and place it in the memory DC. hBmp = CreateCompatibleBitmap(hDCSrc, WidthSrc, HeightSrc) hBmpPrev = SelectObject(hDCMemory, hBmp) ' Get screen properties. RasterCapsScrn = GetDeviceCaps(hDCSrc, RASTERCAPS) ' Raster ' capabilities. HasPaletteScrn = RasterCapsScrn And RC_PALETTE ' Palette ' support. PaletteSizeScrn = GetDeviceCaps(hDCSrc, SIZEPALETTE) ' Size of ' palette. ' If the screen has a palette make a copy and realize it. If HasPaletteScrn And (PaletteSizeScrn = 256) Then ' Create a copy of the system palette. LogPal.palVersion = &H300 LogPal.palNumEntries = 256 r = GetSystemPaletteEntries(hDCSrc, 0, 256, LogPal.palPalEntry(0)) hPal = CreatePalette(LogPal) ' Select the new palette into the memory DC and realize it. hPalPrev = SelectPalette(hDCMemory, hPal, 0) r = RealizePalette(hDCMemory) End If ' Copy the on-screen image into the memory DC. r = BitBlt(hDCMemory, 0, 0, WidthSrc, HeightSrc, hDCSrc, LeftSrc, TopSrc, vbSrcCopy)' Remove the new copy of the on-screen image. hBmp = SelectObject(hDCMemory, hBmpPrev)
' If the screen has a palette get back the palette that was ' selected in previously. If HasPaletteScrn And (PaletteSizeScrn = 256) Then hPal = SelectPalette(hDCMemory, hPalPrev, 0) End If ' Release the device context resources back to the system. r = DeleteDC(hDCMemory) r = ReleaseDC(hWndSrc, hDCSrc) ' Call CreateBitmapPicture to create a picture object from the ' bitmap and palette handles. Then return the resulting picture ' object. Set CaptureWindow = CreateBitmapPicture(hBmp, hPal) End Function''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' CaptureScreen ' - Captures the entire screen. ' Returns ' - Returns a Picture object containing a bitmap of the screen. ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' Public Function CaptureScreen() As Picture Dim hWndScreen As Long ' Get a handle to the desktop window. hWndScreen = GetDesktopWindow() ' Call CaptureWindow to capture the entire desktop give the handle ' and return the resulting Picture object. Set CaptureScreen = CaptureWindow(hWndScreen, False, 0, 0, Screen.Width \ Screen.TwipsPerPixelX, Screen.Height \ Screen.TwipsPerPixelY) End Function''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' CaptureForm ' - Captures an entire form including title bar and border. ' frmSrc ' - The Form object to capture. ' Returns ' - Returns a Picture object containing a bitmap of the entire ' form. '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Function CaptureForm(frmSrc As Form) As Picture ' Call CaptureWindow to capture the entire form given its window ' handle and then return the resulting Picture object. Set CaptureForm = CaptureWindow(frmSrc.hWnd, False, 0, 0, frmSrc.ScaleX(frmSrc.Width, vbTwips, vbPixels), frmSrc.ScaleY(frmSrc.Height, vbTwips, vbPixels)) End Function''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' CaptureClient ' - Captures the client area of a form. ' frmSrc ' - The Form object to capture. ' Returns ' - Returns a Picture object containing a bitmap of the form's ' client area. '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Function CaptureClient(frmSrc As Form) As Picture ' Call CaptureWindow to capture the client area of the form given ' its window handle and return the resulting Picture object. Set CaptureClient = CaptureWindow(frmSrc.hWnd, True, 0, 0, frmSrc.ScaleX(frmSrc.ScaleWidth, frmSrc.ScaleMode, vbPixels), frmSrc.ScaleY(frmSrc.ScaleHeight, frmSrc.ScaleMode, vbPixels)) End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' CaptureActiveWindow ' - Captures the currently active window on the screen. ' Returns ' - Returns a Picture object containing a bitmap of the active ' window. '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Function CaptureActiveWindow() As Picture Dim hWndActive As Long Dim r As Long Dim RectActive As RECT ' Get a handle to the active/foreground window. hWndActive = GetForegroundWindow() ' Get the dimensions of the window. r = GetWindowRect(hWndActive, RectActive) ' Call CaptureWindow to capture the active window given its ' handle and return the Resulting Picture object. Set CaptureActiveWindow = CaptureWindow(hWndActive, False, 0, 0, RectActive.Right - RectActive.Left, RectActive.Bottom - RectActive.Top) End Function''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' PrintPictureToFitPage ' - Prints a Picture object as big as possible. ' Prn ' - Destination Printer object. ' Pic ' - Source Picture object. '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Sub PrintPictureToFitPage(Prn As Printer, Pic As Picture) Const vbHiMetric As Integer = 8 Dim PicRatio As Double Dim PrnWidth As Double Dim PrnHeight As Double Dim PrnRatio As Double Dim PrnPicWidth As Double Dim PrnPicHeight As Double ' Determine if picture should be printed in landscape or portrait ' and set the orientation. If Pic.Height >= Pic.Width Then Prn.Orientation = vbPRORPortrait ' Taller than wide. Else Prn.Orientation = vbPRORLandscape ' Wider than tall. End If ' Calculate device independent Width-to-Height ratio for picture. PicRatio = Pic.Width / Pic.Height ' Calculate the dimentions of the printable area in HiMetric. PrnWidth = Prn.ScaleX(Prn.ScaleWidth, Prn.ScaleMode, vbHiMetric) PrnHeight = Prn.ScaleY(Prn.ScaleHeight, Prn.ScaleMode, vbHiMetric) ' Calculate device independent Width to Height ratio for printer. PrnRatio = PrnWidth / PrnHeight ' Scale the output to the printable area. If PicRatio >= PrnRatio Then ' Scale picture to fit full width of printable area. PrnPicWidth = Prn.ScaleX(PrnWidth, vbHiMetric, Prn.ScaleMode) PrnPicHeight = Prn.ScaleY(PrnWidth / PicRatio, vbHiMetric, Prn.ScaleMode) Else ' Scale picture to fit full height of printable area. PrnPicHeight = Prn.ScaleY(PrnHeight, vbHiMetric, Prn.ScaleMode) PrnPicWidth = Prn.ScaleX(PrnHeight * PicRatio, vbHiMetric, Prn.ScaleMode) End If ' Print the picture using the PaintPicture method. Prn.PaintPicture Pic, 0, 0, PrnPicWidth, PrnPicHeight End Sub'--------------------------------------------------------------------'Save the project. 'Before running this project verify in Project References that a Reference to OLE Automation exists (StdOle2.tlb). 'Run the project and test. You should be able to capture the form, the form's client area, the screen, and the active window. You will also be able to print any of these. 'NOTES: Once you have captured the image you want in a Picture object, you can easily place it on the clipboard using the SetData method of the Clipboard object.
'This article shows how to capture any form or window including the screen into a Visual Basic Picture object. Once the on-screen image is captured in the Picture object, it can easily be printed using the PaintPicture method of the Visual Basic Printer object.
'
'
'MORE Information
'The included example provides several useful routines for capturing images. All of the routines have been written to work under both 16- and 32-bit Windows platforms and they contain full palette support. The routines in the example can:
'Capture the entire contents of a form.
'Capture the client area of a form.
'Capture the entire screen.
'Capture the active window on the screen.
'Capture any portion of any window given a handle to it.
'Create a Picture object from a bitmap and a palette.
'Print a Picture object as large as possible on the page.
'Visual Basic 4.0 introduced a new Picture object. The Picture object is actually a standard OLE type and it is documented in the Control Developer's Kit (CDK.)
'The CDK includes the function OleCreatePictureIndirect that you can use to construct new Picture objects from Visual Basic 4.0. The routine CreateBitmapPicture in the example calls OleCreatePictureIndirect to build a Picture object from a handle to a bitmap and a handle to a palette. If the Picture includes a valid palette, Visual Basic will know to use it when rendering the Picture to the screen or printer. The CreateBitmapPicture routine is used by the CaptureWindow routine to construct Picture objects containing a bitmap of a part or all of a window.
'The CaptureWindow routine in the example captures any portion of a window given a window handle. The routine includes several parameters for describing the exact portion of the window to capture. Capture Window works by copying the on-screen image of a window into a new bitmap. It also checks to see if the screen has a palette and if so it makes a copy of it. CaptureWindow then calls CreateBitmapPicture to construct a bitmap from the newly created bitmap and palette.
'The CaptureForm, CaptureClient, CaptureScreen, and CaptureActiveWindow routines included in the example all use CaptureWindow to capture specific windows. CaptureForm and CaptureClient both call Capture window and pass it the hWnd property of a Form object. CaptureScreen simply gets the handle to the desk top window and calls CaptureWindow. Similarly, CaptureActiveWindow just gets the window handle of the active window and calls CaptureWindow.
'Once the desired image is captured in a Picture object, it is easy to print in Visual Basic 4.0 using the PaintPicture method of the Printer object. The example provides the routine PrintPictureToFitPage that uses the PaintPictureMethod to print the captured images as large as possible in the printable area of the page.
'
'example
'Start a new project. Form1 is created by default.
'Place six CommandButtons on the form along the left side.
'Place one picture box on the form to the right of the buttons.
'Put the following code in Form1:'--------------------------------------------------------------------
' Capture the entire screen.
Private Sub Command1_Click()
Set Picture1.Picture = CaptureScreen()
End Sub' Capture the entire form including title and border.
Private Sub Command2_Click()
Set Picture1.Picture = CaptureForm(Me)
End Sub' Capture the client area of the form.
Private Sub Command3_Click()
Set Picture1.Picture = CaptureClient(Me)
End Sub
' Capture the active window after two seconds.
Private Sub Command4_Click()
MsgBox "Two seconds after you close this dialog " & "the active window will be captured."
' Wait for two seconds.
Dim EndTime As Date
EndTime = DateAdd("s", 2, Now)
Do Until Now > EndTime
DoEvents
Loop
' Set focus back to form.
Me.SetFocus
End Sub' Print the current contents of the picture box.
Private Sub Command5_Click()
PrintPictureToFitPage Printer, Picture1.Picture
Printer.EndDoc
End Sub
Private Sub Command6_Click()
Set Picture1.Picture = Nothing
End Sub
' Initialize the form and controls.
Private Sub Form_Load()
Me.Caption = "Capture and Print Example"
Command1.Caption = "&Screen"
Command2.Caption = "&Form"
Command3.Caption = "&Client"
Command4.Caption = "&Active"
Command5.Caption = "&Print"
Command6.Caption = "C&lear"
Picture1.AutoSize = True
End Sub
Put the following code in the new module:
'--------------------------------------------------------------------
' Visual Basic 4.0 16/32 Capture Routines
' This module contains several routines for capturing windows into a
' picture. All the routines work on both 16 and 32 bit Windows
' platforms.
' The routines also have palette support.
' CreateBitmapPicture - Creates a picture object from a bitmap and
' palette.
' CaptureWindow - Captures any window given a window handle.
' CaptureActiveWindow - Captures the active window on the desktop.
' CaptureForm - Captures the entire form.
' CaptureClient - Captures the client area of a form.
' CaptureScreen - Captures the entire screen.
' PrintPictureToFitPage - prints any picture as big as possible on
' the page.
' NOTES
' - No error trapping is included in these routines.'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Option Explicit
Option Base 0
Private Type PALETTEENTRY
peRed As Byte
peGreen As Byte
peBlue As Byte
peFlags As Byte
End TypePrivate Type LOGPALETTE
palVersion As Integer
palNumEntries As Integer
palPalEntry(255) As PALETTEENTRY ' Enough for 256 colors.
End TypePrivate Type GUID
Data1 As Long
Data2 As Integer
Data3 As Integer
Data4(7) As Byte
End Type Private Const RASTERCAPS As Long = 38
Private Const RC_PALETTE As Long = &H100
Private Const SIZEPALETTE As Long = 104
Private Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type Private Declare Function CreateCompatibleDC Lib "GDI32" (ByVal hDC As Long) As Long
Private Declare Function CreateCompatibleBitmap Lib "GDI32" (ByVal hDC As Long, ByVal nWidth As Long, ByVal nHeight As Long) As Long
Private Declare Function GetDeviceCaps Lib "GDI32" (ByVal hDC As Long, ByVal iCapabilitiy As Long) As Long
Private Declare Function GetSystemPaletteEntries Lib "GDI32" (ByVal hDC As Long, ByVal wStartIndex As Long, ByVal wNumEntries As Long, lpPaletteEntries As PALETTEENTRY) As Long
Private Declare Function CreatePalette Lib "GDI32" (lpLogPalette As LOGPALETTE) As Long
Private Declare Function SelectObject Lib "GDI32" (ByVal hDC As Long, ByVal hObject As Long) As Long
Private Declare Function BitBlt Lib "GDI32" (ByVal hDCDest As Long, ByVal XDest As Long, ByVal YDest As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hDCSrc As Long, ByVal XSrc As Long, ByVal YSrc As Long, ByVal dwRop As Long) As Long
Private Declare Function DeleteDC Lib "GDI32" (ByVal hDC As Long) As Long
Private Declare Function GetForegroundWindow Lib "USER32" () As Long
Private Declare Function SelectPalette Lib "GDI32" (ByVal hDC As Long, ByVal hPalette As Long, ByVal bForceBackground As Long) As Long
Private Declare Function RealizePalette Lib "GDI32" (ByVal hDC As Long) As Long
Private Declare Function GetWindowDC Lib "USER32" (ByVal hWnd As Long) As Long
Private Declare Function GetDC Lib "USER32" (ByVal hWnd As Long) As Long
Private Declare Function GetWindowRect Lib "USER32" (ByVal hWnd As Long, lpRect As RECT) As Long
Private Declare Function ReleaseDC Lib "USER32" (ByVal hWnd As Long, ByVal hDC As Long) As Long
Private Declare Function GetDesktopWindow Lib "USER32" () As Long Private Type PicBmp
Size As Long
Type As Long
hBmp As Long
hPal As Long
Reserved As Long
End Type Private Declare Function OleCreatePictureIndirect Lib "olepro32.dll" (PicDesc As PicBmp, RefIID As GUID, ByVal fPictureOwnsHandle As Long, IPic As IPicture) As Long'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' CreateBitmapPicture
' - Creates a bitmap type Picture object from a bitmap and
' palette.
' hBmp
' - Handle to a bitmap.
' hPal
' - Handle to a Palette.
' - Can be null if the bitmap doesn't use a palette.
' Returns
' - Returns a Picture object containing the bitmap.'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Public Function CreateBitmapPicture(ByVal hBmp As Long, ByVal hPal As Long) As Picture
Dim r As Long
Dim Pic As PicBmp
' IPicture requires a reference to "Standard OLE Types."
Dim IPic As IPicture
Dim IID_IDispatch As GUID
' Fill in with IDispatch Interface ID.
With IID_IDispatch
.Data1 = &H20400
.Data4(0) = &HC0
.Data4(7) = &H46
End With
' Fill Pic with necessary parts.
With Pic
.Size = Len(Pic) ' Length of structure.
.Type = vbPicTypeBitmap ' Type of Picture (bitmap).
.hBmp = hBmp ' Handle to bitmap.
.hPal = hPal ' Handle to palette (may be null).
End With ' Create Picture object.
r = OleCreatePictureIndirect(Pic, IID_IDispatch, 1, IPic)
' Return the new Picture object.
Set CreateBitmapPicture = IPic
End Function
' CaptureWindow
' - Captures any portion of a window.
'
' hWndSrc
' - Handle to the window to be captured.
' Client
' - If True CaptureWindow captures from the client area of the
' window.
' - If False CaptureWindow captures from the entire window.
' LeftSrc, TopSrc, WidthSrc, HeightSrc
' - Specify the portion of the window to capture.
' - Dimensions need to be specified in pixels.
' Returns
' - Returns a Picture object containing a bitmap of the specified
' portion of the window that was captured.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' Public Function CaptureWindow(ByVal hWndSrc As Long, ByVal Client As Boolean, ByVal LeftSrc As Long, ByVal TopSrc As Long, ByVal WidthSrc As Long, ByVal HeightSrc As Long) As Picture
Dim hDCMemory As Long
Dim hBmp As Long
Dim hBmpPrev As Long
Dim r As Long
Dim hDCSrc As Long
Dim hPal As Long
Dim hPalPrev As Long
Dim RasterCapsScrn As Long
Dim HasPaletteScrn As Long
Dim PaletteSizeScrn As Long
Dim LogPal As LOGPALETTE ' Depending on the value of Client get the proper device context.
If Client Then
hDCSrc = GetDC(hWndSrc) ' Get device context for client area.
Else
hDCSrc = GetWindowDC(hWndSrc) ' Get device context for entire window.
End If ' Create a memory device context for the copy process.
hDCMemory = CreateCompatibleDC(hDCSrc)
' Create a bitmap and place it in the memory DC.
hBmp = CreateCompatibleBitmap(hDCSrc, WidthSrc, HeightSrc)
hBmpPrev = SelectObject(hDCMemory, hBmp) ' Get screen properties.
RasterCapsScrn = GetDeviceCaps(hDCSrc, RASTERCAPS) ' Raster
' capabilities.
HasPaletteScrn = RasterCapsScrn And RC_PALETTE ' Palette
' support.
PaletteSizeScrn = GetDeviceCaps(hDCSrc, SIZEPALETTE) ' Size of
' palette. ' If the screen has a palette make a copy and realize it.
If HasPaletteScrn And (PaletteSizeScrn = 256) Then
' Create a copy of the system palette.
LogPal.palVersion = &H300
LogPal.palNumEntries = 256
r = GetSystemPaletteEntries(hDCSrc, 0, 256, LogPal.palPalEntry(0))
hPal = CreatePalette(LogPal)
' Select the new palette into the memory DC and realize it.
hPalPrev = SelectPalette(hDCMemory, hPal, 0)
r = RealizePalette(hDCMemory)
End If ' Copy the on-screen image into the memory DC.
r = BitBlt(hDCMemory, 0, 0, WidthSrc, HeightSrc, hDCSrc, LeftSrc, TopSrc, vbSrcCopy)' Remove the new copy of the on-screen image.
hBmp = SelectObject(hDCMemory, hBmpPrev)
' If the screen has a palette get back the palette that was
' selected in previously.
If HasPaletteScrn And (PaletteSizeScrn = 256) Then
hPal = SelectPalette(hDCMemory, hPalPrev, 0)
End If ' Release the device context resources back to the system.
r = DeleteDC(hDCMemory)
r = ReleaseDC(hWndSrc, hDCSrc) ' Call CreateBitmapPicture to create a picture object from the
' bitmap and palette handles. Then return the resulting picture
' object.
Set CaptureWindow = CreateBitmapPicture(hBmp, hPal)
End Function'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' CaptureScreen
' - Captures the entire screen.
' Returns
' - Returns a Picture object containing a bitmap of the screen.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Public Function CaptureScreen() As Picture
Dim hWndScreen As Long ' Get a handle to the desktop window.
hWndScreen = GetDesktopWindow() ' Call CaptureWindow to capture the entire desktop give the handle
' and return the resulting Picture object.
Set CaptureScreen = CaptureWindow(hWndScreen, False, 0, 0, Screen.Width \ Screen.TwipsPerPixelX, Screen.Height \ Screen.TwipsPerPixelY)
End Function'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' CaptureForm
' - Captures an entire form including title bar and border.
' frmSrc
' - The Form object to capture.
' Returns
' - Returns a Picture object containing a bitmap of the entire
' form.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Function CaptureForm(frmSrc As Form) As Picture
' Call CaptureWindow to capture the entire form given its window
' handle and then return the resulting Picture object.
Set CaptureForm = CaptureWindow(frmSrc.hWnd, False, 0, 0, frmSrc.ScaleX(frmSrc.Width, vbTwips, vbPixels), frmSrc.ScaleY(frmSrc.Height, vbTwips, vbPixels))
End Function'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' CaptureClient
' - Captures the client area of a form.
' frmSrc
' - The Form object to capture.
' Returns
' - Returns a Picture object containing a bitmap of the form's
' client area.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Function CaptureClient(frmSrc As Form) As Picture
' Call CaptureWindow to capture the client area of the form given
' its window handle and return the resulting Picture object.
Set CaptureClient = CaptureWindow(frmSrc.hWnd, True, 0, 0, frmSrc.ScaleX(frmSrc.ScaleWidth, frmSrc.ScaleMode, vbPixels), frmSrc.ScaleY(frmSrc.ScaleHeight, frmSrc.ScaleMode, vbPixels))
End Function
' CaptureActiveWindow
' - Captures the currently active window on the screen.
' Returns
' - Returns a Picture object containing a bitmap of the active
' window.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Function CaptureActiveWindow() As Picture
Dim hWndActive As Long
Dim r As Long
Dim RectActive As RECT ' Get a handle to the active/foreground window.
hWndActive = GetForegroundWindow() ' Get the dimensions of the window.
r = GetWindowRect(hWndActive, RectActive) ' Call CaptureWindow to capture the active window given its
' handle and return the Resulting Picture object.
Set CaptureActiveWindow = CaptureWindow(hWndActive, False, 0, 0, RectActive.Right - RectActive.Left, RectActive.Bottom - RectActive.Top)
End Function'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' PrintPictureToFitPage
' - Prints a Picture object as big as possible.
' Prn
' - Destination Printer object.
' Pic
' - Source Picture object.
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''Public Sub PrintPictureToFitPage(Prn As Printer, Pic As Picture)
Const vbHiMetric As Integer = 8
Dim PicRatio As Double
Dim PrnWidth As Double
Dim PrnHeight As Double
Dim PrnRatio As Double
Dim PrnPicWidth As Double
Dim PrnPicHeight As Double ' Determine if picture should be printed in landscape or portrait
' and set the orientation.
If Pic.Height >= Pic.Width Then
Prn.Orientation = vbPRORPortrait ' Taller than wide.
Else
Prn.Orientation = vbPRORLandscape ' Wider than tall.
End If ' Calculate device independent Width-to-Height ratio for picture.
PicRatio = Pic.Width / Pic.Height ' Calculate the dimentions of the printable area in HiMetric.
PrnWidth = Prn.ScaleX(Prn.ScaleWidth, Prn.ScaleMode, vbHiMetric)
PrnHeight = Prn.ScaleY(Prn.ScaleHeight, Prn.ScaleMode, vbHiMetric)
' Calculate device independent Width to Height ratio for printer.
PrnRatio = PrnWidth / PrnHeight ' Scale the output to the printable area. If PicRatio >= PrnRatio Then
' Scale picture to fit full width of printable area.
PrnPicWidth = Prn.ScaleX(PrnWidth, vbHiMetric, Prn.ScaleMode)
PrnPicHeight = Prn.ScaleY(PrnWidth / PicRatio, vbHiMetric, Prn.ScaleMode)
Else ' Scale picture to fit full height of printable area.
PrnPicHeight = Prn.ScaleY(PrnHeight, vbHiMetric, Prn.ScaleMode)
PrnPicWidth = Prn.ScaleX(PrnHeight * PicRatio, vbHiMetric, Prn.ScaleMode)
End If ' Print the picture using the PaintPicture method.
Prn.PaintPicture Pic, 0, 0, PrnPicWidth, PrnPicHeight
End Sub'--------------------------------------------------------------------'Save the project.
'Before running this project verify in Project References that a Reference to OLE Automation exists (StdOle2.tlb).
'Run the project and test. You should be able to capture the form, the form's client area, the screen, and the active window. You will also be able to print any of these.
'NOTES: Once you have captured the image you want in a Picture object, you can easily place it on the clipboard using the SetData method of the Clipboard object.