Um in Visual Basic 6 einen Screenshot zu erstellen, geht das mit dem folgenden Quellcode sehr einfach. Der Code kann entweder in eine Form benutzt werden oder – was ich empfehle – in ein extra Modul:
Private Declare Function GetDeviceCaps Lib "gdi32" (ByVal hDC As Long, ByVal nIndex As Long) As Long
Private Declare Function GdiplusStartup Lib "GDIPlus" (token As Long, inputbuf As GdiplusStartupInput, Optional ByVal outputbuf As Long = 0) As Long
Private Declare Function GdiplusShutdown Lib "GDIPlus" (ByVal token As Long) As Long
Private Declare Function GdipCreateBitmapFromHBITMAP Lib "GDIPlus" (ByVal hbm As Long, ByVal hPal As Long, Bitmap As Long) As Long
Private Declare Function GdipDisposeImage Lib "GDIPlus" (ByVal Image As Long) As Long
Private Declare Function GdipSaveImageToFile Lib "GDIPlus" (ByVal Image As Long, ByVal FileName As Long, clsidEncoder As GUID, encoderParams As Any) As Long
Private Declare Function CLSIDFromString Lib "ole32" (ByVal str As Long, id As GUID) As Long
Private Declare Function CreateCompatibleDC Lib "gdi32" (ByVal hDC As Long) As Long
Private Declare Function CreateDIBSection Lib "gdi32" (ByVal hDC As Long, pBitmapInfo As BITMAPINFO, ByVal un As Long, ByVal lplpVoid As Long, ByVal handle As Long, ByVal dw As Long) As Long
Private Declare Function SelectObject Lib "gdi32" (ByVal hDC As Long, ByVal hObject As Long) As Long
Private Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long
Private Declare Function DeleteDC Lib "gdi32" (ByVal hDC As Long) As Long
Private Declare Function ReleaseDC Lib "user32" (ByVal hWnd As Long, ByVal hDC As Long) As Long
Private Declare Function GetDIBits Lib "gdi32" (ByVal aHDC As Long, ByVal hBitmap As Long, ByVal nStartScan As Long, ByVal nNumScans As Long, lpBits As Any, lpBI As BITMAPINFO, ByVal wUsage As Long) As Long
Private Declare Function BitBlt Lib "gdi32" (ByVal hDestDC As Long, ByVal X As Long, ByVal Y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal dwRop As Long) As Long
Private Declare Function GetDC Lib "user32" (ByVal hWnd As Long) As Long
Private Const CAPTUREBLT As Long = &H40000000 ' capture layered windows also!
Private Const BI_RGB As Long = 0
Private Const DIB_RGB_COLORS As Long = 0
Private Type BitmapFileHeader
bfType As Integer
bfSize As Long
bfReserved1 As Integer
bfReserved2 As Integer
bfOffBits As Long
End Type
Private Type BitmapInfoHeader
biSize As Long
biWidth As Long
biHeight As Long
biPlanes As Integer
biBitCount As Integer
biCompression As Long
biDataSize As Long
biXPelsPerMeter As Long
biYPelsPerMeter As Long
biClrUsed As Long
biClrImportant As Long
End Type
Private Type RGBQUAD
rgbBlue As Byte
rgbGreen As Byte
rgbRed As Byte
rgbReserved As Byte
End Type
Private Type BITMAPINFO
bmiHeader As BitmapInfoHeader
bmiColors As RGBQUAD
End Type
' mouse cursor
Private Type ICONINFO
fIcon As Long
xHotspot As Long
yHotspot As Long
hbmMask As Long
hbmColor As Long
End Type
Private Type POINTAPI
X As Long
Y As Long
End Type
Private Type PCURSORINFO
cbSize As Long
Flags As Long
hCursor As Long
ptScreenPos As POINTAPI
End Type
Private Declare Function GetCursorInfo Lib "user32.dll" (ByRef pci As PCURSORINFO) As Long
Private Declare Function GetIconInfo Lib "user32.dll" (ByVal hIcon As Long, ByRef PICONINFO As ICONINFO) As Long
Private Declare Function DrawIcon Lib "user32" (ByVal hDC As Long, ByVal X As Long, ByVal Y As Long, ByVal hIcon As Long) As Long
' gdi+
Private Type GUID
Data1 As Long
Data2 As Integer
Data3 As Integer
Data4(0 To 7) As Byte
End Type
Private Type GdiplusStartupInput
GdiplusVersion As Long
DebugEventCallback As Long
SuppressBackgroundThread As Long
SuppressExternalCodecs As Long
End Type
Private Type EncoderParameter
GUID As GUID
NumberOfValues As Long
Type As Long
Value As Long
End Type
Private Type EncoderParameters
Count As Long
Parameter As EncoderParameter
End Type
Public Sub DesktopToJPG(ByVal FileName As String, Optional ByVal Quality As Long = 80, Optional IncludeMouseCursor As Boolean = False)
Dim tSI As GdiplusStartupInput
Dim lRes As Long, lGDIP As Long, lBitmap As Long
Dim X As Long, Y As Long, wide As Long, high As Long
Dim myDIB As Long, myDC As Long, desktopDC As Long
Dim bi24BitInfo As BITMAPINFO
Dim bitmapData() As Byte
Dim pcin As PCURSORINFO
Dim piinfo As ICONINFO
On Error Resume Next
' DPI = 1
' DPI = 1 + RegRead("HKCU\Control Panel\Desktop\PerMonitorSettings\ACI27F4BBLMTF016120_2C_07DB_E8^B94DCAF1BB48BB1AA4C409073022BEE7\DpiValue") * 0.25
'DPI = 1 + 1 * 0.25
DPI = ScreenDPI(True) / 96
' Starting position/Size of capture (full screen)
X = 0: Y = 0
wide = (Screen.Width / Screen.TwipsPerPixelX) * DPI
high = (Screen.Height / Screen.TwipsPerPixelY) * DPI
'
With bi24BitInfo.bmiHeader
.biBitCount = 24
.biCompression = BI_RGB
.biPlanes = 1
.biSize = Len(bi24BitInfo.bmiHeader)
.biWidth = wide
.biHeight = high
.biDataSize = ((.biWidth * 3 + 3) And &HFFFFFFFC) * .biHeight
ReDim bitmapData(0 To .biDataSize - 1)
End With
myDC = CreateCompatibleDC(0)
myDIB = CreateDIBSection(myDC, bi24BitInfo, DIB_RGB_COLORS, ByVal 0&, ByVal 0&, ByVal 0&)
SelectObject myDC, myDIB
desktopDC = GetDC(0)
BitBlt myDC, 0, 0, bi24BitInfo.bmiHeader.biWidth, bi24BitInfo.bmiHeader.biHeight, desktopDC, X, Y, vbSrcCopy Or CAPTUREBLT
' Include mouse cursor?
If IncludeMouseCursor = True Then
pcin.cbSize = Len(pcin)
GetCursorInfo pcin
GetIconInfo pcin.hCursor, piinfo
DrawIcon myDC, pcin.ptScreenPos.X - piinfo.xHotspot, pcin.ptScreenPos.Y - piinfo.yHotspot, pcin.hCursor
If piinfo.hbmMask Then DeleteObject piinfo.hbmMask
If piinfo.hbmColor Then DeleteObject piinfo.hbmColor
End If
Call GetDIBits(myDC, myDIB, 0, bi24BitInfo.bmiHeader.biHeight, bitmapData(0), bi24BitInfo, DIB_RGB_COLORS)
' save as JPG
'------------
'Initialize GDI+
tSI.GdiplusVersion = 1
lRes = GdiplusStartup(lGDIP, tSI)
If lRes = 0 Then
' Create the GDI+ bitmap from the image handle
lRes = GdipCreateBitmapFromHBITMAP(myDIB, 0, lBitmap)
If lRes = 0 Then
Dim tJpgEncoder As GUID
Dim tParams As EncoderParameters
' Initialize the encoder GUID
CLSIDFromString StrPtr("{557CF401-1A04-11D3-9A73-0000F81EF32E}"), tJpgEncoder
' Initialize the encoder parameters
tParams.Count = 1
With tParams.Parameter ' Quality
' Set the Quality GUID
CLSIDFromString StrPtr("{1D5BE4B5-FA4A-452D-9CDD-5DB35105E7EB}"), .GUID
.NumberOfValues = 1
.Type = 4
.Value = VarPtr(Quality)
End With
' Save the image
lRes = GdipSaveImageToFile(lBitmap, StrPtr(FileName), tJpgEncoder, tParams)
' Destroy the bitmap
GdipDisposeImage lBitmap
End If
' Shutdown GDI+
GdiplusShutdown lGDIP
End If
If lRes Then
Err.Raise 5, , "Cannot save the image. GDI+ Error:" & lRes
End If
' CLEAN UP
ReleaseDC 0, desktopDC
DeleteObject myDIB
DeleteDC myDC
End Sub
Public Function ScreenDPI(Optional ByVal Actual As Boolean) As Single
If Actual Then
Dim hDC As Long: hDC = GetDC(0)
ScreenDPI = GetDeviceCaps(hDC, 118) / (Screen.Width / Screen.TwipsPerPixelX)
ReleaseDC 0, hDC
If ScreenDPI = 1 Then
ScreenDPI = 1440! / Screen.TwipsPerPixelX
Else
ScreenDPI = ScreenDPI * 96!
End If
Else
ScreenDPI = 1440! / Screen.TwipsPerPixelX
End If
End Function
Im Parameter FileName gibt man den Pfad an, wo der Screenshot gespeichert werden soll. Im Parameter Quality gibt man die gewünschte Qualität der Bilddatei an (30% oder 100%). Und im Parameter IncludeMouseCursor kann man angeben, ob die Maus ebenfalls aufgenommen werden soll. Die Funktion wird wie folgt aufgerufen:
bilddatei = "screenshot.jpg"
DesktopToJPG bilddatei, 100, True