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下面的方法实际上是抓取屏幕图象的方法。
如果要得到一个PictureBox中的图形（不包括覆盖在其上的控件），可以使用SavePicture Picture1.Picture "c:\test.bmp"语句将图形存盘。这种方法不管整个图形部分是否可见，都可以保存下来。
如果要包括覆盖在其上的控件，可以用下面的办法：
首先建立一个模块，输入以下内容：
Private Type PALETTEENTRY
peRed As Byte
peGreen As Byte
peBlue As Byte
peFlags As Byte
End Type
Private Type LOGPALETTE
palVersion As Integer
palNumEntries As Integer
palPalEntry(255) As PALETTEENTRY ' Enough for 256 colors.
End Type
Private Type GUID
Data1 As Long
Data2 As Integer
Data3 As Integer
Data4(7) As Byte
End Type
#If Win32 Then
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
#ElseIf Win16 Then
Private Const RASTERCAPS As Integer = 38
Private Const RC_PALETTE As Integer = &H100
Private Const SIZEPALETTE As Integer = 104
Private Type RECT
Left As Integer
Top As Integer
Right As Integer
Bottom As Integer
End Type
Private Declare Function CreateCompatibleDC Lib "GDI" ( _
ByVal hDC As Integer) As Integer
Private Declare Function CreateCompatibleBitmap Lib "GDI" ( _
ByVal hDC As Integer, ByVal nWidth As Integer, _
ByVal nHeight As Integer) As Integer
Private Declare Function GetDeviceCaps Lib "GDI" ( _
ByVal hDC As Integer, ByVal iCapabilitiy As Integer) As Integer
Private Declare Function GetSystemPaletteEntries Lib "GDI" ( _
ByVal hDC As Integer, ByVal wStartIndex As Integer, _
ByVal wNumEntries As Integer, _
lpPaletteEntries As PALETTEENTRY) As Integer
Private Declare Function CreatePalette Lib "GDI" ( _
lpLogPalette As LOGPALETTE) As Integer
Private Declare Function SelectObject Lib "GDI" ( _
ByVal hDC As Integer, ByVal hObject As Integer) As Integer
Private Declare Function BitBlt Lib "GDI" ( _
ByVal hDCDest As Integer, ByVal XDest As Integer, _
ByVal YDest As Integer, ByVal nWidth As Integer, _
ByVal nHeight As Integer, ByVal hDCSrc As Integer, _
ByVal XSrc As Integer, ByVal YSrc As Integer, _
ByVal dwRop As Long) As Integer
Private Declare Function DeleteDC Lib "GDI" ( _
ByVal hDC As Integer) As Integer
Private Declare Function GetForegroundWindow Lib "USER" _
Alias "GetActiveWindow" () As Integer
Private Declare Function SelectPalette Lib "USER" ( _
ByVal hDC As Integer, ByVal hPalette As Integer, ByVal _
bForceBackground As Integer) As Integer
Private Declare Function RealizePalette Lib "USER" ( _
ByVal hDC As Integer) As Integer
Private Declare Function GetWindowDC Lib "USER" ( _
ByVal hWnd As Integer) As Integer
Private Declare Function GetDC Lib "USER" ( _
ByVal hWnd As Integer) As Integer
Private Declare Function GetWindowRect Lib "USER" ( _
ByVal hWnd As Integer, lpRect As RECT) As Integer
Private Declare Function ReleaseDC Lib "USER" ( _
ByVal hWnd As Integer, ByVal hDC As Integer) As Integer
Private Declare Function GetDesktopWindow Lib "USER" () As Integer
Private Type PicBmp
Size As Integer
Type As Integer
hBmp As Integer
hPal As Integer
Reserved As Integer
End Type
Private Declare Function OleCreatePictureIndirect _
Lib "oc25.dll" (PictDesc As PicBmp, RefIID As GUID, _
ByVal fPictureOwnsHandle As Integer, IPic As IPicture) _
As Integer
#End If
#If Win32 Then
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
#ElseIf Win16 Then
Public Function CaptureWindow(ByVal hWndSrc As Integer, _
ByVal Client As Boolean, ByVal LeftSrc As Integer, _
ByVal TopSrc As Integer, ByVal WidthSrc As Long, _
ByVal HeightSrc As Long) As Picture
Dim hDCMemory As Integer
Dim hBmp As Integer
Dim hBmpPrev As Integer
Dim r As Integer
Dim hDCSrc As Integer
Dim hPal As Integer
Dim hPalPrev As Integer
Dim RasterCapsScrn As Integer
Dim HasPaletteScrn As Integer
Dim PaletteSizeScrn As Integer
#End If
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
#If Win32 Then
Public Function CreateBitmapPicture(ByVal hBmp As Long, _
ByVal hPal As Long) As Picture
Dim r As Long
#ElseIf Win16 Then
Public Function CreateBitmapPicture(ByVal hBmp As Integer, _
ByVal hPal As Integer) As Picture
Dim r As Integer
#End If
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
只要使用以下语句就可以完成你所要求的任务。
SavePicture CaptureWindow(Picture1.hWnd, False, 0, 0, _
Picture1.ScaleX(Picture1.Width, vbTwips, vbPixels), _
Picture1.ScaleY(Picture1.Height, vbTwips, vbPixels)) _
, "C:\test.bmp"
这时保存的是可见部分，如果要保存不可见的PictureBox中的背景，可以这样：
Picture2.Picture = Picture1.Picture
Picture2.PaintPicture CaptureWindow(Picture1.hWnd, False, 0, 0, _
Picture1.ScaleX(Picture1.Width, vbTwips, vbPixels), _
Picture1.ScaleY(Picture1.Height, vbTwips, vbPixels)), 0, 0
SavePicture Picture2.Picture "c:\test.bmp"
事实上，CaptureWindow可以截取任何窗口的图象。
此问题由李海回答。
附加关键字：编程, 源程序, programming, source code, Visual Basic, VB, 图形、图象, picture, graph, image, draw。
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如何将PictureBox中的图形与控件一起转换为BMP图
